CN101726856B - Onboard goggle-type helmet display optical system - Google Patents
Onboard goggle-type helmet display optical system Download PDFInfo
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- CN101726856B CN101726856B CN2009102514329A CN200910251432A CN101726856B CN 101726856 B CN101726856 B CN 101726856B CN 2009102514329 A CN2009102514329 A CN 2009102514329A CN 200910251432 A CN200910251432 A CN 200910251432A CN 101726856 B CN101726856 B CN 101726856B
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Abstract
The invention discloses an onboard goggle-type helmet display optical system, and provides a large-field optical display system. The optical display system comprises an image source, a relay lens assembly, a prism assembly and a concave surface reflector along optical axis direction in sequence, wherein, the concave surface reflector receives and reflects image light of the image source from the prism assembly; the concave surface reflector has a bending angle corresponding to the image source, thus asymmetric astigmation is generated in the reflection image; the bending angle is defined as an included angle between an optical axis and a normal line of each point of the inner surface of the concave surface reflector; the relay lens assembly is composed of three groups of a front group, a middle group and a rear group; each group respectively comprises a plurality of lens; the front group closes to the prism assembly, the rear group closes to the image source, and the middle group is positioned between the front group and the rear group in the optical axis direction; the three groups of the front group, the middle group and the rear group can be respectively used as a whole to translate and rotate to form a crossing angle between the local area shafts of the front group lens, the middle group lens and the rear group lens, thus compensating the asymmetric astigmation of the optical display system.
Description
Technical field
The present invention relates to catadioptric formula and proofread and correct the optical technology that field, particularly onboard goggle-type helmet display optical system are eliminated aberration, improved picture element from imaging shaft system asymmetric aberration.
Background technology
Onboard goggle-type helmet display to the safety goggles of pilot front, makes the pilot can see the information and the surrounding environment of safety goggles reflection simultaneously the flight parameter information of necessity and aiming information projection.Disclosed canonical correlation patent has U.S.Pat.No.3940204; Goggle-type helmet display in the patent adopts CRT mapping image source; CRT is fixed in a side of the helmet; The CRT images displayed is at first transmitted forward by the relay optical assembly, turns to and projects through prism assemblies then on the curved surface shaped safety goggles, has a bigger angle between the perpendicular line of throw light and safety goggles each point; This angular region has 55 °-60 ° usually, thereby in the safety goggles reflection image, has produced tangible asymmetric aberration.
This asymmetric aberration is very complicated, finds through the analysis of vector Aberration Theory, mainly comprises in the aberration: binode astigmatism and coma, coma be divided into again with the linear composition in visual field and in whole visual field the changeless composition of numerical value; Astigmatism also is divided into the composition that becomes secondary and linear relationship with the visual field, and in whole visual field changeless composition.
Before; Someone proposes between CRT and aviation helmet safety goggles, to introduce with eccentric optical element to constitute the relay optical lens subassembly; Through the asymmetric aberration that optical element tilts or the eccentric aberration that produces is offset the safety goggles Projection Display, the inclination angle of adjusting CRT simultaneously by way of compensation.Be designed to the hologram diffraction face to aviation helmet safety goggles reflecting surface again afterwards, be recorded in the hologram diffraction face before the asymmetrical wave, came further to proofread and correct the asymmetric aberration of safety goggles Projection Display with this.But not success fully of aberration correction effect; Still have tangible residual aberration to exist; In the introducing helmet-mounted display system along with the small-sized flat-panel monitor of broadband, hologram diffraction type safety goggles has become the biggest obstacle of design broadband Helmet Mounted Display on the other hand.But utilize traditional safety goggles to replace hologram diffraction type safety goggles can make asymmetric aberration and chromatic aberration correction difficulty again.The way that another kind reduces asymmetric aberration is to put a beam splitter at pilot's eye face, changes to project the radiation direction on the safety goggles, has therefore reduced the angle between throw light and the safety goggles each point perpendicular line, thereby has reduced asymmetric aberration.But a subject matter of this structure is the eye-point distance that pilot's beam splitter has at the moment obviously reduced airborne Helmet Mounted Display, has limited the application of this structure.
Summary of the invention
The present invention provides a kind of advanced person's airborne helmet goggle-type optical presentation system, and it has bigger visual field and wideer wavelength band, and aberration is little simultaneously, and image quality is high.
The present invention provides a kind of big visual field optical presentation system, and this optical presentation system comprises along optical axis direction successively: the figure image source, and it produces image light; The relay lens assembly is used for the image light that the figure image source produces is transferred to prism assemblies; Prism assemblies is used for the direction of propagation of deflection from the image light of relay lens assembly; Concave mirror; Receive and reflect image light from the figure of prism assemblies image source; There is a bending angle in this concave mirror with respect to the figure image source; Make to generate asymmetric aberration in the reflection image, wherein said bending angle is defined as the angle between optical axis and the concave mirror inside surface each point normal; Said relay lens assembly is made up of for three groups preceding group, middle groups and back group, and wherein each group is made up of a plurality of lens respectively; On optical axis direction, preceding group near said prism assemblies, and the back group is near said figure image source, and middle groups is between preceding group and back group; Before group, middle groups and three groups of lens of back group can be respectively as an integral translation and rotation, make preceding group, middle groups and back three groups of lens local axles of group have an angle of cut each other, thus the asymmetric aberration of compensate for optical display system.
According to an aspect of the present invention, group all has positive focal power with back group lens before said.
Based on one aspect of the present invention, said asymmetric aberration comprises binode astigmatism and coma, through the eccentric of preceding group, middle groups and three groups of lens of back group with tilt to place and it is compensated.
According to an aspect of the present invention, this optical presentation system is operated in the visible wavelength region.
According to an aspect of the present invention, preceding group of said relay optical lens subassembly with back group in comprise the cemented doublet that is used for compensate for optical display system aberration.
According to an aspect of the present invention, comprise a non-spherical lens in the middle groups of said relay optical lens subassembly, be used to proofread and correct the pupil spherical aberration, to increase the pupil image diameter.
The present invention still is a kind of onboard goggle-type helmet optical presentation system, comprising: figure image source, this figure image source are fixed in the side top of the airborne helmet and generate image light; The relay lens assembly is used for the image light that the figure image source produces is transferred to prism assemblies; Prism assemblies is used for the direction of propagation of deflection from the image light of relay lens assembly; Safety goggles as an airborne helmet part; Form concave mirror at this safety goggles inside surface; To receive and to reflect image light from the figure of prism assemblies image source; There is a bending angle in this concave mirror with respect to the figure image source, makes to generate asymmetric aberration in the reflection image, and wherein said bending angle is defined as the angle between optical axis and the concave mirror inside surface each point normal; Said relay lens assembly is made up of for three groups preceding group, middle groups and back group, and wherein each group is made up of a plurality of lens respectively; On optical axis direction, preceding group near said prism assemblies, and the back group is near said figure image source, and middle groups is between preceding group and back group; Before group, middle groups and three groups of lens of back group can be respectively as an integral translation and rotation, make preceding group, middle groups and back three groups of lens local axles of group have an angle of cut each other, thus the asymmetric aberration of compensate for optical display system.
According to an aspect of the present invention, the mode through the semi-transparent semi-reflecting film of plating on said safety goggles inside surface forms concave mirror.
According to an aspect of the present invention, wherein this optical presentation system is operated in the visible wavelength region.
Through the relay optical lens subassembly being divided into preceding group, middle groups and back group, three groups of optical lenses tilt independently of each other and are eccentric, produce binode astigmatism and coma, offset the corresponding aberration of goggle-type optical imaging system.Separate relay lens assembly has increased the degree of freedom of effective compensation asymmetric aberration greatly in three groups, can compensate all three binode astigmatisms and two coma compositions.
In the concrete device of the present invention, preceding group of relay lens assembly has positive focal power, and the helmet wearer pupil is imaged between two lens of middle groups, effectively reduced the bore of whole optical system, claims collimation lens set again for preceding group; Middle groups relay lens assembly is claimed the pupil group again, comprises that a non-spherical lens through proofreading and correct pupil spherical aberration and coma, can effectively increase pupil diameter; Back group relay lens assembly has positive focal power equally, and it will scheme processings that collimate of image that image source generates, to the wearer a tangible far field picture will be provided, after organize the relay lens assembly and just be equivalent to an eyepiece that numerical aperture is bigger.
Use a traditional curved surface safety goggles to replace the hologram diffraction catoptron,, comprised whole visible light wave range in fact basically to increase the waveband width of helmet goggle-type optical presentation system.In order to proofread and correct the aberration that brings thus; All inserted cemented doublet at preceding group with back the group in the relay lens assembly; Positive light coke lens in the group of back place between two cemented doublets in addition, in order that further reduce the bore of back group relay lens assembly, enlarge the diameter of pupil image.Have between figure image source and back group relay lens assembly again and introduced lens, these lens are glued together with the figure image source, and purpose is the curvature of field of proofreading and correct whole optical system, improves the efficiency of light energy utilization of figure image source simultaneously.
Technological merit of the present invention is that the visual field is big, wide waveband, picture element are good, the particularly important is and satisfies the requirement of onboard goggle-type helmet display to optical system.To combine accompanying drawing to be described in detail below.
Description of drawings
Fig. 1 has the airborne helmet top view of goggle-type helmet display system for the present invention;
Fig. 2 has the airborne helmet front view of goggle-type helmet display system for the present invention;
Fig. 3 is the structural drawing of goggle-type helmet display optical system of the present invention;
Embodiment
The present invention describes with helmet demonstration according to airborne pilot, but the present invention can be applied to other many aspects, like " virtual reality " display system, labyrinth analysis and design system etc.
Fig. 1 and Fig. 2 have shown when the present invention is applied to the demonstration of pilot's helmet, the assembly relation of the helmet 1, safety goggles 2 and relay optical lens subassembly 3 of the present invention.Pilot's information display screen is generated by miniature Organic Light Emitting Diode (OLED) display 5; Miniature OLED is contained in the side top of the helmet, carries out deflection through 6 pairs of light of prism assemblies, realizes the information display screen that generates is projected on the safety goggles inside surface; Pilot's eyes are advanced in reflection; Make the pilot see the information display screen that miniature OLED provides, the pilot sees surrounding environment through safety goggles simultaneously, like arrow 7 indications.Group 8, middle groups 9 and back group 10 were installed between miniature OLED display screen 11 and the safety goggles (2) before the relay optical lens component comprised.Fig. 1 and Fig. 2 have provided the sketch of goggle-type helmet display optical system, and optical system more detailed description index map 3 below provides.
Lens layout of the present invention is as shown in Figure 3, and preceding group of the relay optical lens subassembly comprises positive lens 13 and the two gummed of negative lens 14 compositions mirrors, be used for compensating the aberration that broadband is brought, and positive lens 12; Middle groups is made up of non-spherical lens 15 and lens 16; Back group comprises two mirrors that glue together of being made up of positive lens 18 and negative lens 19, and is used for correcting chromatic aberration and positive lens 17 equally; Prism assemblies 6 is used for deflection light, satisfies the requirement of Projection Display.Table 1 has provided the construction data of Fig. 3 optical system, and mm gets in the unit of lens surface curvature radius in the table, and positive number is represented concave curved surface, the negative number representation convex surface; Lens thickness is represented lens front-back center distance, is unit with mm; The refractive index of lens material and Abbe number are used some representation separately in the middle of adopting six traditional numerals, like XXX.YYY, and three the numeral refractive indexes in front, size is 1.XXX; Next three numeral Abbe numbers, size is YY.Y; The front surface of lens representes that with alphabetical F the surface, back is represented with letter r.The radius-of-curvature of safety goggles is 101.2mm, with preceding group in the front surface of positive lens 12 at a distance of 90.6mm; The distance of positive lens 18 was 5mm during miniature OLED display screen was organized to the back.
The tables of data of the specific helmet display optical system of table 1 the present invention
| Lens face | Radius-of-curvature (mm) | Thickness (mm) | Material |
| 6f | ∞ | 25 | 516.641 |
| 6r | ∞ | 2.1 | AIR |
| 12f | -98.55 | -18.2 | 487.701 |
| 12r | 75.62 | -4.2 | AIR |
| 13f | -80.48 | -15.1 | 659.573 |
| 13r/14f | 61.47 | -11.9 | 755.275 |
| 14r | -76.87 | -9.6 | AIR |
| 15f | -60.27 | -13.2 | 753.376 |
| 15r | 62.75 | -5.6 | AIR |
| 16f | 38.5 | -2.2 | 662.354 |
| 16r | 296.8 | -1.2 | AIR |
| 17f | 210.65 | 11.1 | 659.573 |
| 17r | -100.89 | 0.5 | AIR |
| 19f | 57.76 | 12.5 | 602.620 |
| 19r/18f | -42.68 | 11.9 | 755.275 |
| 18r | 809.61 | 8.2 | AIR |
The present invention adopts traditional reflection-type safety goggles, but not hologram diffraction type safety goggles, can satisfy the display requirement of the miniature OLED display of broadband; Helmet display optical system perspective display capabilities is realized through plate semi-transparent semi-reflecting film at the safety goggles inside surface simultaneously.
The optical axis 20 of helmet display optical system is defined as the light path of visual field, center chief ray from miniature OLED display screen to safety goggles; Angle between optical axis and the safety goggles each point normal is called bending angle θ; Can find out difference along with the safety goggles position; The bending angle size changes, between 55 °-60 ° of the normal conditions variation ranges.Just because of safety goggles for the asymmetrical bending angle of incident ray; Caused complicated asymmetric aberration; Comprise the astigmatism that becomes secondary or linear relationship with the visual field and the numerical value astigmatism that immobilizes, and with linear coma in visual field and the numerical value coma etc. that immobilizes.
A key character of the present invention is three groups of lens arrangements that the relay optical lens subassembly is divided into preceding group, middle groups and back group, and preceding group with in the middle of the human eye pupil imaging pupil group, effectively reduces the bore of whole optical system, is equivalent to a telescope; Middle groups is proofreaied and correct pupil spherical aberration and coma, and is very effective to increasing PD; Back group relaying arrives miniature OLED display screen from the light of pupil group, plays the eyepiece effect.Preceding group, middle groups and back group can be carried out transversal displacement with respect to optical axis together or separately, make relay optical lens subassembly misalignment total system optical axis; Group, middle groups and back group also can be carried out tilted deflecting with respect to optical axis together or separately simultaneously, make preceding group, middle groups and back group lens separately the local axle each other, and with the whole optical system optical axis not parallel.
In a word, this structure has increased the degree of freedom of whole optical system greatly, can effectively proofread and correct asymmetric aberration; Simultaneously bandwidth of operation is expanded to visible-range, the apparent field of view angle increases to 30 ° of (level) * 30 ° (vertically), i.e. circular cone visual field 42.42 degree.
Claims (2)
1. big visual field optical presentation system, this optical presentation system is operated in the visible wavelength region, comprises successively along optical axis direction:
The figure image source, it produces image light;
The relay lens assembly is used for the image light that the figure image source produces is transferred to prism assemblies;
Prism assemblies is used for the direction of propagation of deflection from the image light of relay lens assembly;
Concave mirror; Receive and reflect image light from the figure of prism assemblies image source; There is a bending angle in this concave mirror with respect to the figure image source; Make to generate asymmetric aberration in the reflection image, wherein said bending angle is defined as the angle between optical axis and the concave mirror inside surface each point normal;
It is characterized in that: said relay lens assembly is made up of for three groups preceding group, middle groups and back group, and wherein each group is made up of a plurality of lens respectively;
Said asymmetric aberration comprises binode astigmatism and coma, through the eccentric of preceding group, middle groups and three groups of lens of back group with tilt to place and it is compensated;
On optical axis direction, preceding group near said prism assemblies, and the back group is near said figure image source; Middle groups comprises a non-spherical lens between preceding group and back group, be used to proofread and correct the pupil spherical aberration; To increase the pupil image diameter, said preceding group all has positive focal power with back group lens;
Preceding group of the relay optical lens subassembly with the back group in comprise the cemented doublet that is used for compensate for optical display system aberration;
Before group, middle groups and three groups of lens of back group can be respectively as an integral translation and rotation, make preceding group, middle groups and back three groups of lens local axles of group have an angle of cut each other, thus the asymmetric aberration of compensate for optical display system.
2. onboard goggle-type helmet optical presentation system, this optical presentation system is operated in the visible wavelength region, comprises successively along optical axis direction:
Figure image source, this figure image source are fixed in the side top of the airborne helmet and generate image light;
The relay lens assembly is used for the image light that the figure image source produces is transferred to prism assemblies;
Prism assemblies is used for the direction of propagation of deflection from the image light of relay lens assembly;
Goggles as an airborne helmet part; The semi-transparent semi-reflecting film of plating forms concave mirror on this goggles inner surface; With receive and reflection from the image light of the figure image source of prism assemblies; There is an angle of bend in this concave mirror with respect to the figure image source; Make to generate asymmetric aberration in the reflection image, wherein said angle of bend is defined as the angle between optical axis and the concave mirror inner surface each point normal;
It is characterized in that: said relay lens assembly is made up of for three groups preceding group, middle groups and back group, and wherein each group is made up of a plurality of lens respectively; On optical axis direction, preceding group near said prism assemblies, and the back group is near said figure image source; Middle groups comprises a non-spherical lens between preceding group and back group, be used to proofread and correct the pupil spherical aberration; To increase the pupil image diameter, said preceding group all has positive focal power with back group lens;
Said asymmetric aberration comprises binode astigmatism and coma, through the eccentric of preceding group, middle groups and three groups of lens of back group with tilt to place and it is compensated;
Preceding group of the relay optical lens subassembly with the back group in comprise the cemented doublet that is used for compensate for optical display system aberration;
Before group, middle groups and three groups of lens of back group can be respectively as an integral translation and rotation, make preceding group, middle groups and back three groups of lens local axles of group have an angle of cut each other, thus the asymmetric aberration of compensate for optical display system.
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| CN2009102514329A CN101726856B (en) | 2009-12-18 | 2009-12-18 | Onboard goggle-type helmet display optical system |
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| CN2009102514329A CN101726856B (en) | 2009-12-18 | 2009-12-18 | Onboard goggle-type helmet display optical system |
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| CN101726856B true CN101726856B (en) | 2012-06-06 |
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| US9406166B2 (en) * | 2010-11-08 | 2016-08-02 | Seereal Technologies S.A. | Display device, in particular a head-mounted display, based on temporal and spatial multiplexing of hologram tiles |
| WO2012088478A1 (en) * | 2010-12-24 | 2012-06-28 | Chunyu Gao | An ergonomic head mounted display device and optical system |
| CN104884894B (en) * | 2012-02-07 | 2018-05-15 | 株式会社尼康 | Imaging optical system, measurement device, shape measuring apparatus, structure manufacture system and structure manufacture method |
| CN104204906B (en) * | 2012-04-05 | 2017-03-15 | 奥林巴斯株式会社 | Image display |
| CN103399404B (en) * | 2013-08-14 | 2015-10-21 | 中国科学院长春光学精密机械与物理研究所 | Airbornely look type helmet display optical system |
| CN103869472B (en) * | 2014-04-11 | 2016-01-06 | 成都西麦克虚拟现实电子技术有限公司 | Head-up display system and head-up display method thereof |
| CN104142575B (en) * | 2014-08-13 | 2016-04-13 | 中航华东光电（上海）有限公司 | A kind of onboard goggle-type helmet display optical system |
| FR3028325B1 (en) * | 2014-11-06 | 2016-12-02 | Thales Sa | CROSS OPTICAL HEAD VISUALIZATION SYSTEM |
| CN104765150B (en) * | 2015-03-30 | 2017-04-05 | 中国科学院长春光学精密机械与物理研究所 | Using the big visual field helmet display optical system of double ellipsoid structures of rotation-symmetric lenses |
| CN109564380B (en) * | 2016-08-10 | 2022-02-15 | 柯尼卡美能达株式会社 | Projection type display device |
| US11002969B2 (en) | 2018-01-25 | 2021-05-11 | Facebook Technologies, Llc | Light projection system including an optical assembly for correction of differential distortion |
| JP2019144515A (en) * | 2018-02-23 | 2019-08-29 | セイコーエプソン株式会社 | Virtual image display unit |
| KR102570187B1 (en) * | 2019-09-30 | 2023-08-25 | 주식회사 엘지화학 | Head mounted display |
| CN112558292A (en) * | 2020-10-09 | 2021-03-26 | 天津大学 | Small optical system capable of switching virtual and real imaging |
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| US3940204A (en) * | 1975-01-23 | 1976-02-24 | Hughes Aircraft Company | Optical display systems utilizing holographic lenses |
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| US3940204A (en) * | 1975-01-23 | 1976-02-24 | Hughes Aircraft Company | Optical display systems utilizing holographic lenses |
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Owner name: AVIC HUADONG PHOTOELECTRIC CO., LTD. Free format text: FORMER OWNER: HUADONG PHOTOELECTRIC TECHNIQUE INSTITUTE OF ANHUI PROVINCE Effective date: 20110217 |
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Effective date of registration: 20110217 Address after: 241000 Anhui Province, Wuhu city Yijiang District South high tech Development Zone Technology Park mansion Applicant after: Avic Huadong Photoelectric Co., Ltd. Address before: 241000 Anhui Province, Wuhu city Yijiang District South high tech Development Zone Technology Park mansion Applicant before: Huadong Photoelectric Technique Institute of Anhui Province |
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