WO2004041096A2

WO2004041096A2 - Mobile endoscopic video system

Info

Publication number: WO2004041096A2
Application number: PCT/US2003/034210
Authority: WO
Inventors: Michael Burnett; Jimmy Sayavong; Kurt Kappus
Original assignee: Smith & Nephew, Inc.
Priority date: 2002-10-30
Filing date: 2003-10-28
Publication date: 2004-05-21
Also published as: AU2003295360A1; WO2004041096A3; AU2003295360A8

Abstract

A mobile endoscopic video system (100) includes a case body (110) that includes a light source (1710), circuitry used for endoscopic imaging, a first port (530) that allows communication between the circuitry used for endoscopic imaging and a camera head (1003), a second port (526) that receives a light guide (905) able to guide light from the light source (1710) to a scope assembly (1015) coupled to the camera head (1003), and a third port (800). The mobile endoscopic video system (100) further includes a display (500) mounted on the case body (110) and able to receive image data from the third port (800) of the case body, display images based on the image data, and fold onto the case body (110) for system transport.

Description

MOBILE ENDOSCOPIC VIDEO SYSTEM

TECHNICAL FIELD This application relates to endoscopic video systems in general and to mobile endoscopic video systems in particular.

BACKGROUND Endoscopic imaging systems are commonly used for viewing internal organs for diagnostic or minimally-invasive surgical procedures. An endoscopic imaging system includes at least a light source, a camera, and a display screen.

SUMMARY In one general aspect, a mobile endoscopic video system includes a case body and a display mounted on the case body. The case body includes a light source, circuitry used for endoscopic imaging, a first port that allows communication between the circuitry used for endoscopic imaging and a camera head, a second port that receives a light guide able to guide light from the light source to a scope assembly coupled to the camera head, and a third port. The display is able to receive image data from the third port of the case body, display images based on the image data, and fold onto the case body for system transport. Implementations may include one or more of the following features. For example, the image data may be a video signal in PAL or NTSC format. The case body may include a removable cover and a handle for system transport.

The light source may be mounted on a removable tray that slides out of the case body to allow manual replacement of the light source. The case body may include a mechanism to shut-off power to the system when the tray slides out of the case body. The system may further include a light source lifetime indicator. The system may include a camera head connected to the first port by a cable. The camera head may include a light receiving surface for receiving an optical signal from a target of interest and signal processing circuitry for converting the optical signal into a video signal. The camera head also may include buttons that control accessories to the system. The accessories to the system may include at least one of a video cassette recorder, a video print recorder, or a digital capture system.

The system may further include at least one port able to send to an external video device a video signal based on the image data. The format of the video signal includes at least one of composite and Y/C. The external video device may include a video cassette recorder, a video print recorder, or a digital capture system. The circuitry for endoscopic imaging may include circuitry that prevents simultaneous power up of both the light source and the display so as to prevent a system power drain. The display may be attached to the case body by hinges and able to flip up from the case body. The display may also be enclosed under a removable cover connected to the case body. In another general aspect, a mobile endoscopic video system includes a camera head, a light guide, a scope assembly coupled to the camera head and the light guide, a cable coupled to the camera head, a case body, and a display mounted on the case body. The case body includes a handle for system transport, a removable cover, a light source, circuitry used for endoscopic imaging, a first port that receives the cable and allows communication between the circuitry used for endoscopic imaging and the camera head, a second port that receives the light guide so that the light guide is able to guide light from the light source to the scope assembly, and a third port. The display receives image data from the third port of the case body, displays images based on the image data, and folds onto the case body for system transport.

Other features will be apparent from the description, the drawings, and the claims.

DESCRIPTION OF DRAWINGS

Fig. 1 shows a perspective view of an endoscopic mobile video unit in travelling mode.

Fig. 2 shows a right side view of the endoscopic mobile video unit of Fig. 1. Fig. 3 shows a back view of the endoscopic mobile video unit of Fig.

1.

Fig. 4 shows a front view of the endoscopic mobile video unit of Fig.

1. Fig. 5 shows a front side of the endoscopic mobile video unit of Fig.

1 in operating mode.

Fig. 6 shows a right side view of the endoscopic mobile video unit of

Fig. 1 in operating mode.

Fig. 7 shows a back view of the endoscopic mobile video unit of Fig. 1 in operating mode.

Fig. 8 shows a close up of the view of Fig. 7 excluding the display unit.

Fig. 9 shows a perspective view of the endoscopic mobile video unit of Fig. 5 with an attached endoscope assembly. Figs. 10 is a view of a camera head/scope assembly.

Fig. 11 is a view of a camera head.

Fig. 12 is a cross-sectional view of a front module of a camera head of Figs. 10 and 11.

Fig. 13 is another cross-sectional view of the front module of Fig. 12. Fig. 14 is an assembly drawing of the camera head of Figs. 10 and

11.

Figs. 15A, 15B, 15C, 15D, 15E, 15F and 15G show a system level circuit diagram of the endoscopic mobile video unit of Fig. 1.

Fig. 16 is a top view of the endoscopic mobile video unit of Fig. 1 without a cover and with selected internal components visible. Fig. 17 is another top view of the endoscopic video unit of Fig. 1 without a cover and with selected internal components visible. Fig. 18 is an assembly drawing of the endoscopic video unit of Fig. 1 without a cover and with selected internal components visible. Fig. 19 is a perspective view of the endoscopic video unit of Fig. 1 without a cover and with selected internal components visible. Fig. 20 is an assembly drawing of a display unit of the endoscopic mobile video unit of Fig. 1.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION Referring to Figs. 1-4, an endoscopic mobile video unit 100 in travelling mode includes a case cover 105 and a case body 110. The case body 110 includes a left side 115 having a handle 120 to facilitate carrying the mobile video unit 100. The case cover 105 is attached to the case body 110 by a first pair of latches 125 that extend from the left side 115 and a second pair of latches 225 (Fig. 4) that extend from the right side 200. The case body right side 200 includes two vents 205 that serve to ventilate the inside of the case body for cooling purposes. Two rest pads 210 made of a solid, impact- absorbing material, such as rubber, are attached to the right side 200 and allow the mobile video unit 100 to stand left side up and right side down without damage. Four bumpers 215 made of an impact-absorbing material such as rubber are attached to the case body bottom 220 and positioned so as to protect the mobile video unit 100 from damage when the bottom is in contact with a surface such as the floor or a table top, typically during operation of the mobile video unit. Referring to Figs. 5-7, the endoscopic mobile video unit 100 is transitioned to operating mode by completely removing the case cover 105 from the case body 110 and flipping up a display unit 500. The case cover 105 is removed by unlatching the two latches 125 on the left side 115 and the two latches 225 on the right side 200 of the case body. An endoscope assembly 900 (Fig. 9) is then attached to the endoscopic mobile video unit 100 prior to use. The endoscope assembly 900 is carried in a separate container or duffle bag when the mobile video unit 100 is in travelling mode. The display unit 500 includes a flat panel display 505 and is attached to the case body top 510 by four hinges 515. Each of the four hinges 515 is attached to the flat panel display 505 by two screws 517. When the case cover 105 is removed, the display unit 500 is lying flat on the case body top 510 such that the flat panel display 505 is coplanar with the top and facing away from the case body 110. The hinges 515 allow the display unit 500 to flip up from the top 510 for easy viewing. The display unit 500 includes display controls 520 that are used to fine-tune the flat panel display image. The display unit 500 is a module of the mobile video unit 100 and is designed to be removable. The hinges 515 are configured to allow easy removal of the display unit for remote placement or to substitute the unit for another when upgrading. To remove the display unit 500, an operator unscrews the screws 517 from the hinges 515. The display unit 500 is electrically connected to the case body 110 by a ground cable 1915 and a video/power cable 1920 attached to a threaded L-shaped cable connector 1925 (Fig. 19). The ground cable is attached to the display unit 500 by screw 1917. The L-shaped cable connector 1925 is screwed into a threaded connector (not shown) in the case body top 510. The ground cable 1915 and the video/power cable 1920 may be extendible to allow remote placement of the display unit 515. The display unit is small and lightweight and can be placed at a remote location for easier viewing including placement within the surgical sterile field. This flexibility enhances use of the endoscopic mobile video unit 100 by reducing the potential for eyestrain and enabling the display unit 500 to be located near the surgeon's hands. The display unit may be a high resolution liquid crystal display (LCD) and may be easily upgraded with LCDs that have higher resolution or brightness as such LCDs become available. Fig. 8 is a close-up view of the back side 300 of the case body 110 with the display unit 500 removed. Fig. 9 shows the mobile video unit 100 with an attached endoscope assembly 900 used for operations.

Referring again to Fig. 5, the front side 400 includes the various buttons, knobs, and connectors that together form the user control panel 522 for operation of the mobile video unit 100. Specifically, the panel 522 includes a power switch 524, a light guide port 526 and latch 528, a camera cable receptacle 530, a white set button 532, a lamp indicator 534, a white set indicator 536, a shutter control knob 540, and a lamp access hatch 538. The power switch 524 may be any standard switch and turns the mobile video unit on or off. A standard rocker switch is shown. The light guide port 526 is a self-closing light guide port designed to accept a light guide 905. The light guide is inserted or removed from the port by pressing the latch 528. The camera cable receptacle 530 is configured to receive a connector 910 of a camera cable 915. The receptacle shown is a push-in, keyed receptacle.

The white set button 532 automatically adjusts the camera of the camera head/scope assembly 920 for optimal white balance when pressed while the camera is focused on a white object. A completion "beep" or another indicator may be used to communicate when the white set is complete.

The lamp indicator 534 is used to visually communicate when the lamp 1710 (Fig. 17) of the mobile video unit 100 is ready for use and when the lamp 1710 needs to be changed. The lamp indicator 534 may be a light-emitting diode (LED) that flashes after the system is turned on or after power interruption and turns off when the lamp 1710 is ready for use. The LED may also stay continuously lit rather than turn off to indicate that the lamp 1710 is old and needs to be changed. The white set indicator 536 is used to indicate when the white set process is occurring. The indicator may be an LED that is lit when the camera is in the white set process. The illumination may be terminated when the white set is complete. The shutter control knob 540 is used to control the amount of illumination that passes through the light guide port 526. The shutter control knob 540 mechanically changes the position of a shutter (not shown) that increasingly obstructs the lamp 1710 and thereby decreases the intensity of the light. The light intensity may be increased or decreased by turning the knob clockwise or counterclockwise.

The lamp access hatch 538 provides access to the lamp 1710 of the mobile video unit for lamp replacement. The hatch is configured to allow access without requiring any tools. In one example, access is achieved by unscrewing a knob 542 by hand and pulling out a lamp assembly tray 1715 (Fig. 17).

Referring to Fig. 8, the back side 300 contains video outputs 800, an input power receptacle 805, an accessory controls interface 810, a lamp hour reset 815, a NTSC/PAL switch 820, and two cooling fan assemblies 825.

The video outputs 800 provide video data for peripheral video recording and/or display devices. As an example, the video outputs shown in Fig. 8 include one composite (BNC) and two Y/C standard video connections. The former can be used to connect to an external slave monitor or VCR and the latter can be used to connect to an external S-VHS VCR, video print recorder, or digital capture system.

The input power receptacle 805 is a receptacle that accepts a standard connector from a hospital grade power cord. The receptacle 805 is electrically connected to two fuses 830 that serve as circuit breakers in the event of a power overload. The accessory controls interface 810 provides communication control from the buttons on the camera head 1003 (Fig. 10) to video accessories. As an example, two output plugs are shown in Fig. 8. These may be used to connect to a digital capture system and allow capture of still images when one button on the camera head is pressed and allow video capture when another button on the camera head is pressed. The lamp hour reset 815 is a reset button that allows the user to reset the lamp hour memory to "0" when a new lamp is installed. Setting the lamp hour memory enables monitoring of the lamp life to aid in determining when a replacement might be needed. The lamp indicator 534 references the lamp hour memory to determine when it should visually indicate that the lamp 1710 needs to be replaced. In this example, the lamp indicator 534 will illuminate after 500 hours. The NTSC/PAL switch 820 changes the output video format of the built-in color bar generator that displays a standard colorbar image when no camera head is connected. The NTSC/PAL switch 820 must be set to the same format position as the camera head (i.e., it must be set to PAL with a PAL head). The two fan assemblies 825 provide cooling to the mobile video unit system. The fan assemblies along with the vents 205 on the case body right side 200 allow air to circulate within the case body and cool the internal components of the mobile video unit. Referring to Fig. 9, the attached endoscope assembly 900 includes the light guide 905, the camera cable 915, and the camera head/scope assembly 920.

The camera cable 915 provides all necessary electrical connections between the camera head/scope assembly 920 and the case body 110. The camera cable 915 has a connector 910 used to attach the cable to the camera cable receptacle 530 on the front side 400 of the case body 110. The connector 910 has a soak cap 925 that is placed over the connector 910 and locked when the cable is disconnected from the case 110. The soak cap 925 prevents moisture and corrosion buildup around pins of the connector, as such moisture and corrosion can cause the connectors and the camera system to fail. The camera cable is long enough to provide the surgeon with ample room to move around during operation. In one example, the camera cable is 12 feet long. Similarly, the light guide 905 provides a light path from the lamp 1710 within the case body 110 to the camera head/scope assembly 920. The light guide 905 is typically a fiber-optic cable and is connected to the camera head/scope assembly 920 by a cylindrical fiber optic connector 930. The light guide 905 is connected to the case body 110 by a light guide adaptor 935 that mates with the light guide port 526.

Referring to Figs. 10 and 11, the camera head/scope assembly 920 includes a camera head 1003 consisting of a rear module 1005 and a front module 1010 , a scope assembly 1015, and a cable connector 1020. The front module includes two buttons 1025 that may be pressed by the user to enable certain functions as discussed above.

Figs. 12 and 13 show two different cross sections of the front module 1010 of the camera head/scope assembly 920. Fig. 14 shows a perspective assembly drawing of the camera head/scope assembly 920. Referring to Figs. 12 and 14, the front module 1010 includes a housing 1200 composed of a chemically resistant medical plastic (e.g., polyethertherketone (PEEK)) able to withstand the rigors of a hospital environment and repeated sterilization cycles. The housing 1200 defines a mount 1202 used to mount the scope assembly 1015 to the front module 1010. The mount 1202 may be, for example, a standard 1-inch, 32-thread c-mount. The scope assembly 1015 includes a direct view scope 1017 and a coupler 1019. The direct view scope 1017 is a standard component that directs light from the wave guide 930 into the point of insertion within a patient's body and directs reflected light back to the front module 1010 via the coupler 1019. Rod lenses are typically within the direct view scope 1017 to focus and direct light. The coupler 1019 optically couples the direct view scope 1017 to the front module 1010 for imaging. The direct view scope 1017 and the coupler 1019 may be integrated into a single unit.

Window 1206 covers a circular hole 1204 defined by the housing and adjacent to the mount 1202. The window 1206 may be made of glass capable of withstanding hospital environmental conditions and may be attached to the housing 1200 by, for example, epoxy. The window 1206 allows light to enter the front module 1010 while preventing any elements from the outside environment from reaching the sensitive electronics in the front module 1010. The housing 1200 defines a cylindrical void 1208. The width x of the cylindrical void 1208 is chosen to ensure that the image generated by the mounted scope assembly 1015 is positioned at an optimal focal distance from a CMOS sensor chip 1210 of CMOS sensor board 1212. The housing 1200 also defines a purge hole 1214 that allows the void 1208 to be purged of all oxygen and filled with nitrogen after assembly of the front module 1010. This purging prevents condensation on the surface of the window 1206 and on the surface of the CMOS sensor chip 1210 that may occlude the detected image. Once the purge is complete, the purge hole 1214 is threaded and sealed by a purge screw 1400 and washer 1401 (Fig. 14).

Machined washer 1216 abuts the cylindrical void 1208 and the CMOS sensor chip 1210. The washer 1216 collects dust inside the front module 1010 and prevents the dust from collecting on the CMOS sensor chip 1210 and obscuring the detected image. Light from the scope assembly 1015 reaches the CMOS sensor chip

1210 through the mount 1202, the circular hole 1204, the window

1206, the void 1208, and the cup 1216. The CMOS sensor board

1212 is fastened to the housing 1200 by two bolts 1218. The bolts pass through holes 1220 in the CMOS sensor board 1212. The bolts may be made, for example, from milled steel. Spacers 1222 circumferentially enclose the bolts 1218 and serve to hold the CMOS sensor board 1212 in its position.

Connector board 1224 attaches to CMOS sensor board 1212 using connector 1226. The connector board 1224 is fastened to the housing 1200 by the same two bolts 1218 used to fasten the CMOS sensor board 1212 to the housing 1200. The bolts extend through holes 1228 in the connector board 1224. Spacers 1230 circumferentially enclose the bolts 1218 and serve to hold the connector board 1224 in its position. Washers 1232 mechanically buffer the connector board 1224 from the heads of the bolts 1218. O-ring 1234 is used to form an air-tight shield between the front module 1010 and the rear module 1005. O-ring 1234 may be made of a standard composite material for o-rings used in the medical equipment industry (e.g., ethylene propylene-EPDM).

Fig. 13 shows a cross-section of the front module 1010 similar to that of Fig. 12 but rotated 90 degrees. For clarity, neither the circuit boards 1212 and 1224 nor the machined washer 1216 are shown. Two pins 1300 are inserted in the housing 1200. The pins 1300 have barbed portions 1305 that extend from the housing 1200. The pins extend through the circuit boards 1212 and 1224 through cutouts 1405 (Fig. 14). The pins 1300 are used to secure, via an interference fit, the front module 1010 to the rear module 1005 and are pushed into receptacles 1410 mounted on a housing 1415 of the rear module 1005. The pins may be made of a light-weight, durable material, such as, for example, aluminium.

Referring to Figs. 11 and 14, the rear module 1005 includes a housing 1415 that mates with housing 1200 of the front module

1010. The rear module 1005 is also connected to the camera cable 915 by threaded cable connector 1020. The cable connector 1020 screws into the rear module 1005. The camera cable 915 is electrically connected to the circuit boards 1220 and 1224 by ground wire 1100 and flex circuit 1105. Figs. 15A, 15B, 15C, 15D, 15E, 15F and 15G shows a system level circuit diagram 1500 of the mobile video unit system 100. The circuitry of the mobile video unit system 100 resides in the camera head 1003, the case body 110, and the display unit 500. The circuitry 1502 in the camera head 1003 resides on circuit boards 1212 and 1224. The case body circuitry includes a head connector board 1504, a colorbar board 1506, an hour reset board 1508, a white set board 1510, a power supply 1512, a relay board 1514, a lamp ballast board 1516, an accessory control board 1518, a rear output board 1520, an enhancement board 1522, and a microprocessor board 1524. The display unit circuitry includes a liquid crystal display board 1526 and a display control board 1528. The camera head circuitry 1502 includes the CMOS sensor chip 1210 and its support circuitry. In many camera heads of endoscopic video systems, the sensor resides in the camera head and the signals that drive the sensor (e.g., clock signals, horizontal/vertical drives, signals that coordinate the timing of image data outputs) originate in the control unit and are sent to the sensor in the camera head through the camera cable. Unprocessed image data is then sent back from the camera head to the control unit over the same camera cable. The circuitry 1502 in the camera head of the mobile video unit system 100 is different than the circuitry in most camera heads in that it is capable of processing the image data and, therefore, does not require many of the sensor drive signals sent from the control unit or case body 110. By integrating much of the signal processing in the camera head, fewer signals travel over the camera cable 915, and, therefore, the mobile video unit 100 is more resistant to system failure caused by damage to the camera cable 915. This greater resilience is particularly important for a mobile system because of the increased possibility of damage from repeatedly moving the system from location to location and using the system in unpredictable environments.

The circuitry in the camera head 1502 collects the image data through the sensor chip 1210 and processes the image data into standardized video signals. Specifically, the image data is processed into standard Y-C video signals and a standard composite signal and sent to the microprocessor board 1524 through Y, C, and COMP pins, respectively. The video signals may be sent out either in NTSC format or PAL format depending on the video format of the sensor chip. The sensor chip may be a CMOS sensor chip, such as the OV7910P available from Omnivision of Sunnyvale California.

The microprocessor board circuitry 1524 also communicates with the circuitry 1502 in the camera head through the SDA, SCL,

CBCC, SW1, and SW2 pins. The microprocessor board 1524 coordinates and configures the image sensing circuitry 1502 in the camera head through the SDA and SCL pins.

The CBCC signal is a binary logic level signal used to communicate to the microprocessor board 1524 the status of the connection between camera head 1003 and the case body 110. When the camera head 1003 is disconnected from the case body 110, the microprocessor board 1524 detects that the camera head 1003 is disconnected through the CBCC signal and sends a colorbar image from the colorbar board 1506 to the display unit 500.

The SW1 and SW2 signals are binary logic signals that toggle, for example, from a high potential to a low potential when the buttons in the camera head 1025 are pressed. The SW1 and SW2 signals are sent to the microprocessor board 1524 to control relays that control accessories to the mobile video system 100 through connections on the accessory control board 1518. The CMOS sensor chip 1210 is in the CMOS sensor board 1212 and the support electronics are spread among the CMOS sensor board 1212 and the connector board 1224. The Y, C, COMP, SDA, SCL, SW1, SW2, and power supply (12VDC) signals are sent from the CMOS sensor board 1212 and the connector board 1224 to the cable connector 1020 and, in turn, to the camera cable 915 through the flex circuit 1105 (Fig. 11 ). The ground signals are sent to the cable connector 1020 and the camera cable 915 through the ground conductor 1100 (Fig. 11).

The head connector board 1504 is a pass-through board designed to support the camera cable receptacle 530. All signals exchanged between the microprocessor board 1524 and the camera head board 1502 pass through the head connector board 1504 without being processed.

The colorbar board 1506 generates a colorbar video signal and sends the colorbar video signal to the microprocessor board 1524 through a VIDEO pin of the colorbar board 1506. The microprocessor board 1524 sends the colorbar video signal to the display unit 500 if the camera head 1003 is not connected to the case body. If the value of the CBCC signal received from the head connector board 1504 indicates that the camera head 1003 is not connected to the case body 110, the microprocessor board 1524 sends the colorbar signal to the display unit 500 through a VIDEO pin of a JP13 connector. If, on the other hand, the value of the CBCC signal received from the head connector board 1504 indicates that the camera head is connected, the microprocessor board 1524 uses the VIDEO pin of the JP11 connector to send the composite video signal received to the display unit 500 through the COMP pin of the head connector board 1504.

When the display unit 500 receives the colorbar video signal, an image of color bars is generated on the display 505. The color bars correspond to standard colors (i.e., bars with fixed and predetermined color values) and may be used by the operator to verify that the mobile video system 100 is working properly and to adjust the display settings using display controls 520 to ensure that the standard colors are represented properly on the display 505. The colorbar board 1506 is able to generate the colorbar video signal in both NTSC and PAL formats depending on the potential appearing at the NTSC/PAL SEL pin. The potential of the NTSC/PAL SEL pin is determined by the position of the NTSC/PAL switch 820 of the hour reset board 1508. The hour reset board 1508 includes the circuitry for the hour reset button 815 and the NTSC/PAL switch 820. The hour reset board 1508 sends an hour reset signal to the microprocessor board 1524 through the HR RESET pin. The hour reset signal is a logic signal that may be pulled, for example, to a low potential when the hour reset button 815 is pressed. When the hour reset signal is pulled low, a timer programmed in software accessible to a microprocessor 1523 (not shown) in the microprocessor board 1524 starts a countdown. The duration of the countdown corresponds to an estimate of the lifetime of a new lamp 1710 (Fig. 17) of a lamp assembly 1700 (Fig. 17). The duration of the countdown may be, for example, 500 hours. Once the countdown is completed, the microprocessor board 1524 sends a LAMP LED signal to the white set board 1510 that activates the lamp indicator 534 on the user control panel 522. The lamp indicator 534 informs the operator that the lamp 1710 needs to be replaced. The NTSC/PAL switch 820 allows the user to select the format of the colorbar video signal generated by the colorbar board 1506. The NTSC/PAL switch 820 should be toggled by the operator such that the format of the colorbar video signal corresponds to the format of the video signals (i.e., NTSC and PAL) generated by the camera head 1003.

The white set board 1510 includes the circuitry for the white set button 532, the lamp indicator 534, and the white set indicator 536. The white set button 532 is pressed by the operator to calibrate the colors of the sensor chip 1210 to different light conditions. Typically, the operator aims the camera head 1003 at a white object in the environment and presses the white set button 532. The white set board 1510 then sends a WS SWITCH signal to the microprocessor board 1524 to indicate that the white set button 532 has been pressed. The microprocessor 1523 of the microprocessor board 1524 sends instructions to perform a white set operation to the sensor chip 1210 of the camera head board 1502 through the SDA and SCL pins. The white set operation may take 2-5 seconds. The white set board 1510 receives a WS LED signal from the microprocessor board 1524 to indicate that the white set operation is in progress. The WS LED signal is a logic signal that activates the white set indicator 536 when, for example, the WS LED signal is at a high potential. The WS LED signal may be pulled to a high potential when the operator presses the white set button 532 and then kept at a high potential by the circuitry in the microprocessor board 1524 for a predetermined amount of time equal to a conservative estimate of the duration of the white set operation. Alternatively, the WS LED signal may be pulled to a high potential when the operator presses the white set button and then may return to a low potential when the camera head board 1502 sends a signal to the microprocessor board 1524 through the SDA and SCL pins indicating that the white set operation is completed. The microprocessor board 1524 then pulls the WS LED signal to a low potential to turn off the white set indicator 536. The white set indicator 536 may stay continuously lit or, alternatively, may continuously blink during the white set operation.

The white set board 1510 also includes the circuitry that supports the lamp indicator 534 used to inform the operator when the lamp 1710 of the mobile video unit 100 needs to be replaced. When the LAMP LED signal is, for example, pulled to a high potential by the microprocessor board 1524, the lamp indicator 534 is activated and may light up or continuously blink to inform the operator that the lamp 1710 needs to be replaced. When the LAMP LED signal is pulled to a low potential by the microprocessor board 1524, the lamp indicator 534 does not light or blink, which informs the operator that the lamp 1710 does not need to be replaced. The power supply board 1512 accepts a power signal ranging from 85 volts AC up to 265 volts AC through the power receptacle 805. As discussed below with respect to Fig. 16, the power signal is sent from the power receptacle 805 through an interlock or interconnect switch 1616, through the power switch 524, and through fuses 1800 prior to being received by the power supply board 1512. The power supply board converts the power signal to a 12 volt DC signal that is sent to the microprocessor board 1524, the relay board 1514, and the enhancement board 1522. The 12 volt DC signal is also sent to the liquid crystal display board 1526, the display control board 1528, the colorbar board 1506, and the head connector board 1504 through the microprocessor board 1524. The 12 volt DC signal is also sent to the circuitry in the camera head 1502 through the head connector board 1504 and to the fans 825, the fan 1530 of the lamp assembly 1700, and the lamp ballast board 1516 through the relay board 1514.

The relay board 1514 receives a 12 volt DC signal from the power supply board 1512 and distributes the 12 volt DC signal into two 12 volt DC signals that are sent to power the fans 825 and the fan 1530 of the lamp subassembly. The relay board 1514 includes a relay (not shown) that is powered by a 5 volt DC power signal from the microprocessor board 1524 and is controlled by a LAMP ON logic signal from the microprocessor board 1524. The relay (not shown) accepts a 12 volt DC input from the power supply board 1512 through pin +12V (IN). When the LAMPJDN signal is, for example, pulled to a high potential by the microprocessor board 1524, the relay is closed and pin +12V (IN) is connected to pin +12V (OUT). The 12 volt DC signal is thereby connected to the lamp ballast board 1516 to allow the lamp 1710 to receive power and be turned on. The LAMP_ON signal is used in the mobile video unit 100 to limit the current drawn from the power supply board 1512 when the mobile video unit 100 is first turned on. The LAMP DN signal is not pulled to a high potential until a predetermined time after the mobile video unit 100 is turned on. This delay in turning on the lamp 1710 prevents the lamp 1710 from draining current from the power supply board 1512 during startup.

The lamp ballast board 1516 is a power supply board that converts the 12 volt DC signal received from the relay board 1514 into a power signal capable of powering the lamp 1710. The lamp 1710 may be, for example, a 60W short-arc gas-filled lamp with approximately a 500 hour lifetime and 6,500 K color temperature. The accessory control board 1518 sends control signals to accessories attached to the mobile video unit 100 through the accessory controls interface 810. The accessory controls interface may include two output plugs J1 and J2. The output plugs may be, for example, phone jack connectors. The J1 connector includes two conductors - one of which is electrically connected to SW1 A and one of which is electrically connected to SW1B. The J2 connector includes two conductors similarly connected to SW2A and SW2B. The microprocessor board 1524 includes a relay (not shown) that connects SW1A and SW1B to each other or disconnects SW1A and

SW1B from each other depending on the value of the logic signal

SW1 received from the head connector board 1504. When the operator, for example, presses a button 1025 on the camera head 1003, the SW1 signal may be pulled to a low potential to cause the relay (not shown) to connect SW1A to SW1B. When the button

1025 is no longer pressed, the SW1 signal may be pulled to a high potential to cause the relay to sever the connection between SW1 A and SW1B. The accessory attached to J1 senses the connection or disconnect between SW1A and SW1B and thereby detects when the button 1025 on the camera head 1003 is pressed. The accessory then performs whatever function corresponds to that button being pressed. A second accessory attached to J2 may behave in an analogous manner upon an operator pressing a second button 1025 on the camera head 1003.

The rear output board 1520 includes connectors that provide the video outputs 800 to peripheral video recording and display devices. The video outputs 800 include two duplicate Y/C video outputs and one composite video output. The duplicate Y/C video outputs are provided by the microprocessor board 1524 through the Y1 , C1 , Y2, and C2 pins. The composite video output is provided by the microprocessor board 1524 through the VIDEO pin. The enhancement board 1522 increases the detail characteristics of the image by processing the standard Y/C video signals and the composite video signal. The image data received by the microprocessor board 1524 from the head connector board 1504 is sent to the enhancement board 1522 through the Yin, Cin, and COMPin pins. The Y/C signals and the composite video signal are processed by the enhancement board 1522 and then sent back to the microprocessor board 1524 through the Yout, Cout, and COMP- OUT pins. The processing of the video signals sharpens the image by performing standard enhancement algorithms such as adding artificial contrast to detail in the image. The microprocessor board 1524 includes eight dipswitches (not shown) that may be toggled to control the processing characteristics of the enhancement board 1522. Each of the eight dipswitches may be physically toggled to set the binary logic level of a corresponding signal CTL0 to CTL7 that is sent to the enhancement board 1522. Three of the dipswitches may be used to set the noise characteristics of the signal. Two of the dipswitches may be used to set the contrast of the image, and two more may be used to set the background brightness. One dipswitch may be used as a bypass switch that allows the signals to bypass the enhancement board 1522 without being processed. The eight dipswitches on the microprocessor board 1524 are initially set during assembly of the mobile video unit 100. An operator rarely changes these initial settings.

The display unit 500 includes the liquid crystal display board 1526 and the display control board 1528. The liquid crystal display board 1526 receives a composite video signal and a 12 volt DC power signal from the microprocessor board 1524 through the connector 1532. Connector 1532 mates with the threaded L-shaped cable connector 1925 (Fig. 19) that is attached to the video/power cable 1920 (Fig. 19). The video/power cable 1920 is, in turn, connected to the display unit 500 and electrically connected to both the liquid crystal display board 1526 and the display control board 1528. The display control board 1528 receives power from the liquid crystal display board 1526 and receives a FPD ON/OFF signal from the microprocessor board 1524. The FPD ON/OFF signal is similar in function to the LAMP ON signal discussed previously. The FPD ON/OFF signal is a binary logic signal that turns on the display unit 500 after the mobile video unit 100 has been turned on for a predetermined period. The delay between turning on the unit 100 and turning on the display unit 500 limits the current drain from the power supply 1512 during the initial power up of the unit 100. The display control board 1528 may turn on the liquid crystal display board 1526 when, for example, the FPD ON/OFF is at a high potential and may turn off the liquid crystal display board 1526 when the FPD ON/OFF signal is at a low potential. The display control board 1528 includes circuitry that supports the display controls 520. The display control board 1528 sends to the liquid crystal display board 1526 control signals that fine tune the display image. The control signals may change, for example, the brightness, contrast, and position of the image on the display 505. The liquid crystal display board may be an LC-150M2U liquid crystal display manufactured by Sharp.

The microprocessor board 1524 is the main processing board of the mobile video unit 100. The microprocessor board 1524 includes the microprocessor 1523 (not shown) and various peripheral support circuitry. The microprocessor board 1524 calibrates and configures the camera using the microprocessor 1523 through the SDA and SCL pins (e.g., sets and calibrates brightness levels and color levels). The microprocessor board 1524 includes circuitry capable of switching the image video signals sent to the display unit 500 from the image signals generated by the camera head board 1502 to the colorbar video signals generated by the colorbar board 1506. The circuitry switches the image signals when the CBCC signal indicates that the camera head 1003 is disconnected. The circuitry switches the signals back when the CBCC signal indicates that the camera head 1003 is once again connected.

The microprocessor board 1524 provides the power up signals LAMP ON and FPD ON/OFF that turn on the lamp 1710 and the display unit 500 in sequence at a specified time after the mobile video unit 100 is initially turned on. The microprocessor board 1524 provides the additional video outputs 800 to the rear output board 1520, provides a timer for the lamp indicator 534 and the white set indicator 536, provides relays that control accessories connected to the unit 100 through the accessory control board 1518, and provides enhancement level settings that control the processing of the image done in the enhancement board 1522.

Fig. 16 shows the interior of the case body 110 and the arrangement of the various internal electronic components used in the mobile video unit 100. The interior components include an input power receptacle 805 that accepts a standard connector from a hospital grade power cord (not shown) that allows the mobile video unit 100 to accept power from an external source (not shown). The power receptacle 805 may be a standard IEC connector for medical devices (i.e., it may accept power signals from 85 volts AC up to 265 volts AC). A ground conductor 1602, a power conductor 1604, and a neutral conductor 1606 extend from the power connector 1600. The ground conductor 1602 is connected to the case body 110 by a screw 1608. The power conductor 1604 and the neutral conductor 1606 are wound around a ferrite bead 1610 to decrease noise in the power signal.

The power conductor 1604 and the neutral conductor 1606 are electrically connected to pin 1612 and pin 1614 of interconnect switch 1616, respectively. The interconnect switch 1616 has a button 1618 that may be pressed to establish an electrical connection between pin 1612 and pin 1620, and between pin 1614 and pin 1622 of the interconnect switch 1616. Pin 1620 is connected to power conductor 1624, and pin 1622 is connected to neutral conductor 1626. During normal operation, button 1618 is pressed by the lamp assembly 1700 (Fig. 17), which results in power conductor 1604 being electrically connected to power conductor

1624 and neutral conductor 1606 being electrically connected to neutral conductor 1626. When the button 1618 is pressed, the mobile video unit 100 receives power from the external power source through power conductor 1624. However, if an operator removes the lamp assembly 1700 in order to, for example, replace the lamp 1710, the button 1618 is no longer pressed by the assembly 1700 and the connection between the power conductor

1604 and the power conductor 1624 and between the neutral conductor 1606 and the neutral conductor 1626 is severed. In this manner, the interconnect switch 1616 serves as a safety cut-off mechanism that shuts off the power to the unit 100 and prevents possible electrocution of the operator when the operator removes the lamp assembly 1700. The power conductor 1624 and the neutral conductor 1626 are electrically connected to the power switch 524. When the power switch 524 is switched to ON, the power conductor 1624 is electrically connected to the power conductor 1628 and the neutral conductor 1626 is electrically connected to the neutral conductor 1630. When the power switch 524 is switched to OFF, the connections between the conductors 1624 and 1628 and between the conductors 1626 and 1630 are severed. The power switch 524 is connected to fuses 1800 (Fig. 18) that prevent power overloads from damaging downstream components of the mobile video unit 100. Power conductor 1628 and neutral conductor 1630 are electrically connected to power supply board 1512. The power supply board 1512 is connected to the case body 110 by screws 1633 that screw into threaded stand-offs (not shown) attached to the case body 110. The relay board 1514 splits the power from the power supply board 1512 to service the two cooling fan assemblies 825, the fan 1530 of the lamp assembly 1700, and the lamp ballast board 1516. The relay board 1514 is connected to the case body 110 by screws 1635 that screw into threaded stand-offs (not shown) attached to the case body 110.

The microprocessor board 1524 is the main processing board for the mobile video unit 100 and is connected to the case body 110 by screws 1637 that screw into threaded standoffs (not shown) attached to the case body 110. The enhancement board 1522 accepts the video signal from the microprocessor board 1524, processes the video signal in order to improve the image, and returns the processed signal to the microprocessor board 1524. The enhancement board 1522 is connected to the case body 110 by screws 1639 that screw into threaded standoffs (not shown) attached to the case body 110. The colorbar board 1506 interfaces with the microprocessor board 1524 and the hour reset board 1508 (Fig. 18). The colorbar board 1506 is electrically connected to the NTSC/PAL switch 820 through the lamp hour reset board 1508 (Fig. 18). The colorbar board 1506 is connected to case body 110 by screws 1641 that screw into threaded standoffs (not shown) attached to the case body 110. Referring to Figs. 15, 16, 17, and 19, the lamp assembly 1700 includes a guide assembly 1642, the lamp ballast board 1516, the lamp 1710, the lamp assembly tray 1715, and the lamp cooling fan 1530. The tray 1715 holds the lamp 1710, the lamp ballast board 1705, and the lamp cooling fan 1530. The user may open the lamp access hatch 538 and pull out the lamp assembly tray 1715 as necessary when the lamp 1710 needs to be replaced. Referring to Fig. 18, the rear output board 1520 is mounted to the back side 300 of the case body 110 by a bracket 1810. The bracket is mounted to the back side 300 by screws 1815 that are screwed into threaded standoffs 1820 attached to the back side 300. The rear output board 1805 provides the video outputs 800. The lamp hour reset board 1508 is mounted to the back side 300 by screws 1830 that are screwed into threaded standoffs 1835. The lamp hour reset board 1508 includes the lamp hour reset button 815 and the NTSC/PAL switch 820 discussed previously. An accessory control board 1518 is mounted to the back side 300 of the case body 110 by screws 1845 that are screwed into threaded standoffs 1850. The accessory control board 1518 is electrically connected to the accessory controls interface 810 discussed previously. Referring to Fig. 19, the head connector board 1504 is mounted to the front side 400 of the case body 110 by the camera cable receptacle 530. The white set control board 1510 is mounted to the front side 400 of the case body 110 by screws 1910 that are screwed into threaded standoffs (not shown). The white set control board 1510 includes the white set button 532, the white set indicator 536, and the lamp indicator 534.

Fig. 20 shows an assembly drawing of the display unit 500. The display unit 500 includes a front enclosure 2000, the display controls 520, the display control board 1528, a shielded window 2005, foam padding 2010, the flat panel display board 1526, a rear enclosure 2015, and a cushion strip 2020. The display controls 520 include control buttons 2025 that extend through holes 2030 in front enclosure 2000 and also extend through a control overlay 2035 that is attached to front enclosure 2000. The buttons 2025 are electrically connected to the display control board 1528. The display control board 1528 is attached to the front enclosure 2000 by screws 2040 that are screwed into threaded stand-offs 2042 extending from the front enclosure 2000.

Flat panel display board 1526 sandwiches shielded window 2005 and foam padding 2010 against front enclosure 2000. The display board 1526 is attached to front enclosure 2000 by hex nuts 2047 that screw into stand-offs 2048 through washers 2050. The standoffs 2048 are attached to pins 2049 extending from the front enclosure 2000. The rear enclosure 2015 is attached to the front enclosure 2000 by screws 2052 that may be screwed into threaded standoffs 2054 and by screws 2056 that may be screwed into threaded holes 2058 in rear enclosure 2015. A bushing 2060 connects video/power cable 1920 to rear enclosure 2015.

The cushion strip 2020 is made of an impact-absorbing material and is used to prevent damage to the mobile video unit 100 caused by the impact of the display unit 500 against the case body top 510 when the display unit 500 is forcefully flipped down. What is claimed is:

Claims

1. A mobile endoscopic video system comprising: a case body including a light source, circuitry used for endoscopic imaging, a first port configured to allow communication between the circuitry used for endoscopic imaging and a camera head, a second port configured to receive a light guide able to guide light from the light source to a scope assembly coupled to the camera head, and a third port; and a display mounted on the case body and configured to receive image data from the third port of the case body, display images based on the image data, and fold onto the case body for system transport.

2. The system of claim 1 wherein the image data is a video signal in PAL or NTSC format.

3. The system of claim 1 wherein the case body further includes a handle for system transport.

4. The system of claim 1 wherein the case body further includes a removable cover.

5. The system of claim 1 further comprising a light source lifetime indicator.

6. The system of claim 1 wherein the light source is mounted on a removable tray configured to slide out of the case body to allow manual replacement of the light source.

7. The system of claim 6 wherein the case body further includes a mechanism to shut-off power to the system when the tray slides out of the case body.

8. The system of claim 1 further comprising a camera head connected to the first port by a cable.

9. The system of claim 8 wherein the camera head includes a light receiving surface for receiving an optical signal from a target of interest and signal processing circuitry for converting the optical signal into a video signal.

10. The system of claim 8 wherein the camera head includes buttons that control accessories to the system.

11. The system of claim 10 wherein the accessories to the system include one or more of a video cassette recorder, a video print recorder, and a digital capture system.

12. The system of claim 1 wherein the case body further includes at least one port configured to send a video signal based on the image data to an external video device.

13. The system of claim 12 wherein the format of the video signal includes at least one of composite and Y/C.

14. The system of claim 12 wherein the external video device includes a video cassette recorder, a video print recorder, or a digital capture system.

15. The system of claim 1 wherein the circuitry for imaging includes circuitry that prevents simultaneous power up of both the light source and the display so as to prevent a system power drain.

16. The system of claim 1 wherein the display is attached to the case body by hinges and is able to flip up from the case body.

17. The system of claim 1 wherein the display is configured to be enclosed under a removable cover connected to the case body.

18. A mobile endoscopic video system of claim 1 further comprising: a camera head; a light guide; a scope assembly coupled to the camera head and the light guide; and a cable coupled to the camera head.

19. The system of claim 18 wherein the image data is a video signal in PAL or NTSC format.

20. The system of claim 18 further comprising a light source lifetime indicator.

21. The system of claim 18 wherein the light source is mounted on a removable tray configured to slide out of the case body to allow manual replacement of the light source.

22. The system of claim 21 wherein the case body further includes a mechanism to shut-off power to the system when the tray slides out of the case body.

23. The system of claim 18 wherein the camera head includes a light receiving surface for receiving an optical signal from a target of interest and signal processing circuitry for converting the optical signal into a video signal.

24. The system of claim 18 wherein the camera head includes buttons that control accessories to the system.

25. The system of claim 18 wherein the case body further includes at least one port configured to send a video signal based on the image data to an external video device.

26. The system of claim 25 wherein the format of the video signal includes at least one of composite and Y/C.

27. The system of claim 18 wherein the circuitry for imaging includes circuitry that prevents simultaneous power up of both the light source and the display so as to prevent a system power drain.

28. The system of claim 18 wherein the display is attached to the case body by hinges and is able to flip up from the case body.