MOBILE PHONE WITH LASER RANGE FINDER.
The field of the invention
The present invention is related to a portable range finder including a laser device.
Background of the invention
There are many different situations in which someone wants to be able to estimate and measure distances in an easy and handy way. One example of such a situation is when a golf player wants to know, how far he or she is from green to be able to choose the right club. Another example is when architects for example want to know the exact distance between two houses.
One way to measure distances is by means of a range finder, e.g. of the kind shown in patent document US 2002/0067475 and EP 0 686 857. These documents show a range finder, which uses a camera to generate a picture on a display, and where the distance to an object is measured by pointing the camera lens towards the object. This type of range finder is often rather expensive due to the need of a camera. Another disadvantage with a range finder of this type is that it is a relatively large device, which the user has to carry along and this device cannot be used for other purposes either, than just range finding. This implies that an average user, who as a rule already has several devices to carry along, e.g. a mobile phone, a digital calendar, a notebook, is forced to carry yet another device.
Another way to measure distances is by means of GPS (Global Positioning System) . Known GPS-devices have however the same disadvantages as the range finders mentioned above, i.e. they
are rather space demanding and therefore not completely comfortable to bring along everywhere. There is a method for measuring distance in golf contexts, which method uses GPS. Before a range finding is performed, the whole golf course must be put into the device as a map, which is a time- consuming step. Further, this method is not completely reliable, but has rather high measure tolerances, and functions best in clear views, i.e. when it is nice weather. It also takes a couple of minutes before the result is shown on a display and a user may experience that as a rather long time.
There is thus a need for a range finder, which by users are deemed as handy to carry along, and which can show the result of a desired range measure in a fast way and with high accuracy and that also is economical.
Summary of the invention
It is an object of the present invention to provide a range finder that solves the problems mentioned above.
In accordance with the present invention this is achieved by a range finder of LADAR type (Laser Detection and Ranging) , which can be compressed to take up only a very little space, for instance on an integrated circuit, through which the range finder in an easy and handy way can be connected to a portable handheld device, such as a mobile or a PDA (Personal Digital Assistant) . The display and the keyboard of the portable handheld device can be used for interaction between the user and the range finder. Conventional portable handheld devices of this kind usually also include a battery, which also can be utilized by the range finder.
By using the display of the handheld device to show the result of a range finding the result can be presented for a user in an easy way. The results can principally be shown in real time, whereby time-consuming waiting is avoided. Furthermore, by using the keyboard of the handheld device, which already is well known and familiar to the user, this provides an advantage in using an effective user interface.
According to another preferred embodiment the range finder comprises a connection interface to a portable handheld device. Thereby the range finder can, in an easy way, be connected to a portable handheld device, when there is a need for range finding. But it can also be disconnected from the portable handheld device, when there is no need for range finding.
According to another preferred embodiment, a picture received from of the laser device can be transformed to a format that can be shown on the display of the portable handheld device. Thereby the user is enabled to see a picture on the display of the area including the object to which the distance is to be measured. The user can thereby in an easy way aim the range finder at the object.
According to another preferred embodiment, the range finder may include software in order to enable zooming of the area. A marker, or cursor, is shown on the display, which furthermore simplifies for the user to aim the range finder at a desired object. When the marker is in line with the zoomed object, the range finder is instructed to measure the distance.
According to yet another preferred embodiment, the portable handheld device is a mobile phone or a handheld computer
(PDA) . These are devices that many users already have. More than half of the population in Sweden has a mobile phone and this figure is increasing very fast. The fact that a range finder may be connected to, or integrated with, a mobile phone without considerably increase its size or weight, is thus a very useful improvement. In a few years it is estimated that more camera mobiles will be sold compared to usual digital cameras.
According to a second aspect of this invention, the objects are achieved by means of a range finder of LADAR type (Laser Detection and Ranging) , which can be compressed to take up only a very little space, for instance placed on an integrated circuit. In that way, the range finder may be integrated with a portable handheld device, e.g. a mobile or a handheld computer (PDA) . The display and the keyboard of the portable handheld device can be used for interaction between the user and the range finder. Conventional portable handheld devices of this kind often include a battery, which also in this embodiment can be utilized by the range finder.
The housing of the portable handheld device must in this embodiment be provided with at least one opening through which the laser beam, which is generated by the laser device, can be emitted and received in order to measure a desired distance.
Further advantages are obtained by different aspects of the invention and will become clear from the following detailed description.
A brief description of the drawings
Fig. 1 shows a portable handheld device in the form of a mobile with which a range finder is integrated.
Fig. 2 shows a portable handheld device in the form of a mobile phone, where the range finder is a separate module.
Detailed description of preferred embodiments
As mentioned earlier there are several situations, in which a range finder would be a desired and very useful device. A golf player, who wants to know distance between a ball and green can according to this invention pick up his/hers mobile phone with an integrated or connected range finder. The golf player then sees a picture of the golf course on the display of the mobile and aims it at the flag on green or another suitable object and then presses a button, whereby a laser beam is emitted, hits the flag and a signal is sent back to the mobile. All this happens within hundreds of a second. The distance between the ball and the flag is calculated and shown on the display. Also this is performed very fast, near real time.
Besides in the context of golf, there are several other applications, where a handy device for range finding is desirable, for example when sailing, mountain climbing, photographing or hunting.
The present invention uses preferably a LADAR (Ladar Detection and Ranging) principle. In this application a laser beam is emitted to scan a geographic area called a scanning pattern. Each such pattern is generated by repeatedly scanning vertically and at the same time scanning horizontally. Data are received from the reflected signal and are processed in the laser device. Speed and the angle for a sensor compared to the horizon can create a picture of the environment, where each pixel in the picture corresponds to a reflected beam. The
technology behind the LADAR-system is known and will not be discussed in detail in this application.
In order to integrate this laser radar technology within a portable handheld device, for instance a cellular phone, without increasing its size and weight very much, the laser radar functions must be integrated into a component like micro system, where all basic parts (laser diode, photo receiver, receiving channel (s), electronics for measuring time intervals, and so on) can preferably be placed on just one circuit. But this can not be done at the expense of the performance of the system. Research is being done within this area, and it has been shown that power control elements may be eliminated. There are today commercially available LADAR circuits on the market, which may be used to create this range finding device.
According to an embodiment of the present invention such a circuit is integrated with at portable handheld device. In the following description a mobile phone will be used in order to illustrate the invention. This invention is however not limited to mobiles, and the range finder can also be integrated with or be connected to other types of portable handheld devices, for instance a handheld computer (PDA) .
The laser technology that this invention utilizes is not in any way dangerous for human beings . A human being can for instance look into a laser beam during a long time without being affected at all. The affects from laser have earlier been a problem in different applications.
With reference to figure 1 a mobile 1 is shown with a housing 2, a keyboard 3, a display 4 and an antenna 6 and other parts
conventionally included in a mobile. In the mobile 1 there is a range finder of LADAR type integrated (not shown) . In order for a laser beam to be emitted from the mobile 1 its housing 2 must include at least one opening 5, situated underneath of the mobile 1. This is indicated in the figure with broken rectangles. In alternative embodiment these openings 5' are placed on the short side of the mobile 1. It is realised that the openings are preferably placed so that a user can aim the mobile 1 at an object to which the distance will be determined and at the same be able to look at the display 4 of th.e mobile 1 in a convenient way. The placing of these openings is in other aspects not important for the invention.
By aiming the mobile 1 at an object and press a button 7, or in another way indicate that a range finding is to be done, a laser beam is emitted, reflected and received by the mobile 1, as was described above in connection to the description of the LADAR technology. Data for the received signal are processed and when this is done, a picture 8 can be generated and shown on the display 4 of the mobile 1. The user thus sees a picture of the area, which the mobile 1 is aimed at, and the user can, in an easy way, aim the mobile 1 at a desired object. An indicator or marker of some kind can advantageously be shown on the display 4 in order to facilitate for the user to hit the object with the laser beam. This marker can for instance be in the form of a cross 9 and when the cross is overlying the wanted object the range finding is executed.
The received picture can be manipulated in several ways. It is for instance possible to rotate the picture on the display 90 degrees, which may be useful if the height of the display is larger than its width.
In a mobile 1 the range finding is preferably included as an application in the menu of the mobile 1. A user can here choose in which mode the mobile 1 shall be in, which is explained more in detail below.
According to another preferred embodiment of the present invention a camera can be used in order to create a picture of the environment, and with the help of which the range finding can be done. This kind of mobile, with a built-in digital camera, is already on the market. In this embodiment a user can zoom at the object to which the distance is to be measured. The zooming can be done in several steps, so that the object appears closer and closer. By means of this application the user can, in an easy way, zoom and measure the distance to the wanted object.
After the execution of a range measurement the distance to the object is calculated and the result is shown on the display 4. This can be done almost in real-time and a user will get the result very fast compared to the state of the art, where a user must wait several minutes to get a result. Measured distances can be stored in a memory and be retrieved, when needed. A user can in this way make a number of measurements and then process and use the results at a later moment. It is also possible to perform other functions than range finding. It is for instance possible to measure the sizes of surfaces, the distance between two selected objects and also the volume of a selected object. Different professionals can in this way use their combined range finder and mobile phone in accordance with this invention in their professional activities. A real estate broker can for instance measure the size of the rooms of an object that is going to be sold, or the size of a vacant site. Architects can measure the distance between houses and
other distances that they may need in their professional activities.
According to an alternative embodiment, shown in fig. 2, the range finder is not integrated with the portable handheld device, but is designed as a separate module 10, which includes an interface for connection to a mobile 1. The mobile 1 comprises, in this embodiment, an interface for connection to a range finder 10. Also the range finder 10 includes an interface for connection to mobile 1. This interface preferably consists of a standardized interface, which today is used by several units connectable to mobiles. When the portable handheld device consists of other devices than mobiles (e.g. a handheld computer or a staff locator (pager)) a corresponding interface is used. By using this separate plug-in unit 10 the battery of the mobile 1 can be used and the unit 10 can be made very small and only include a LADAR module and software for calculating distances. It can further, as was described above in connection to the integrated embodiment, also include software for achieving zooming of an area. In another embodiment this software is included in the mobile phone at the manufacture of the same. In this embodiment the housing of the mobile need not include openings 5 for the laser beam. These openings can, in this embodiment, instead be located on the separate module.
The mobile 1 must however be arranged to be connectable to the separate module 10 and by means of this connection, which can be mechanical and electrical, transfer information from this module. The information that the mobile receives from the separate unit 10 includes data, which are transformed to a picture of the environment, which can be shown on the display of the mobile, as was explained above, and also data in order
to show the result from the range measurment. The mobile is thus somewhat modified in order for a range finder to be connectable to the mobile. The mobile includes for instance software in order to show pictures and the result from the range finding on the display of the mobile. It is not excluded that the range finder includes software that affect a conventional handheld device without any modifications to cooperate with the range finder.
As was mentioned above, it should be possible to choose in which mode a mobile should be in. Earlier there was a description of a golf player. It may be unsuitable for the player to have the mobile in a call mode, i.e. a ringing mode, since the player may be punished with an extra stroke, if the mobile rings during play. According to this invention a mobile 1 with an integrated or connectable range finder can be in different modes. In a first mode the mobile functions as a normal phone, i.e. it can receive calls and handle outgoing calls, but it cannot be used as a range finder. In a second mode the mobile functions as a range finder with the call function closed. This is the mode that a golf player would want to use. In a third mode both the call function and range finding function can be used at the same time, i.e. a user can receive and make calls at the same as a range finding is performed.
Preferably the present invention uses a LADAR module, which has been described above. It should be possible to measure up to 500 meters, which for most applications is enough. But also longer distances can be measured by using a stronger laser, which enables applications in which larger distances need to be measured, for instance when sailing. The range finder in accordance with the present invention can replace a normal
measuring tape, i.e. it should be possible to make accurate measurements at relatively short distances.
As was mentioned above, it is a requirement that the LADAR module can be made very small in order for it to be integrated in a portable handheld device without affecting the size and weight of said portable handheld device. The LADAR module should also be inexpensive, making the range finder attractive for a large market. It is thus favourable, if the LADAR can be fitted on an integrated circuit, IC.
There are several ways in order to get the wanted circuit. "Passively Q-switched microchip laser" is one technology that could be used. VCSEL (Vertical Cavity Surface Emitting Laser) is another one. Nanotechnology is a further alternative that can be used to produce a very compact laser radar. But there is also MEMS technology (Micro Electronic Mechanical Systems) that can be used, which is an instrument on a micro level. MEMS is mechanical systems created in a process called micro machining process. This process includes almost the same steps, when the integrated circuits are manufactured. Other technologies than these mentioned above can also be suitable.