EP0746782A1 - Intensified visual display - Google Patents

Intensified visual display

Info

Publication number
EP0746782A1
EP0746782A1 EP94922412A EP94922412A EP0746782A1 EP 0746782 A1 EP0746782 A1 EP 0746782A1 EP 94922412 A EP94922412 A EP 94922412A EP 94922412 A EP94922412 A EP 94922412A EP 0746782 A1 EP0746782 A1 EP 0746782A1
Authority
EP
European Patent Office
Prior art keywords
quarter
image light
wave plate
light
polarized image
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP94922412A
Other languages
German (de)
French (fr)
Other versions
EP0746782A4 (en
Inventor
Richard Dennis Rallison
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
VIRTUAL I/O Inc
Virtual I O Inc
Original Assignee
VIRTUAL I/O Inc
Virtual I O Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by VIRTUAL I/O Inc, Virtual I O Inc filed Critical VIRTUAL I/O Inc
Publication of EP0746782A1 publication Critical patent/EP0746782A1/en
Publication of EP0746782A4 publication Critical patent/EP0746782A4/xx
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/017—Head mounted
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/017—Head mounted
    • G02B27/0172—Head mounted characterised by optical features
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
    • G02B27/283—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising used for beam splitting or combining
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0118—Head-up displays characterised by optical features comprising devices for improving the contrast of the display / brillance control visibility
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0132—Head-up displays characterised by optical features comprising binocular systems
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0138—Head-up displays characterised by optical features comprising image capture systems, e.g. camera
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0143—Head-up displays characterised by optical features the two eyes not being equipped with identical nor symmetrical optical devices
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0179—Display position adjusting means not related to the information to be displayed
    • G02B2027/0187—Display position adjusting means not related to the information to be displayed slaved to motion of at least a part of the body of the user, e.g. head, eye
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B2027/0192—Supplementary details
    • G02B2027/0198—System for aligning or maintaining alignment of an image in a predetermined direction
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/02—Simple or compound lenses with non-spherical faces
    • G02B3/08—Simple or compound lenses with non-spherical faces with discontinuous faces, e.g. Fresnel lens
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements

Definitions

  • TECHNICAL FIELD This invention relates to visual display which combine generated images with the view of the environment surrounding a user and transmit such combined visual information to the eye position of the user.
  • Such a display requires, in a form known as a folded catadioptric display, an image generator; a beam splitter, which receives the image light from the image generator and sends a fraction, designated the reflected fraction, of such image light to a reflective combiner that both allows light from the real world to pass through such combiner and reflects the image light such that both the real-world light and the image light are transmitted to the eye of the user through the beam splitter.
  • the beam splitter will transmit a fraction, designated the transmitted fraction, of the image light reflected from the collimator-combiner.
  • the transmitted fraction a fraction of the image light reflected from the collimator-combiner.
  • a correction lens is often placed in the optical path between the image generator and the beam splitter.
  • the light emitted from liquid crystal displays is linearly polarized because liquid crystal displays utilize polarizers to modulate amplitude.
  • the only cathode ray tubes which produce linearly polarized light are those which are colored with an active wave plate, such as the Tektronics Pi cell, all of the light from which is linearly polarized.
  • a fold mirror When a fold mirror is selected as the beam splitter, it is plastic or glass having, preferably, a dielectric or holographic dichromated gelatin coating. Metal coatings are unacceptable because the fold mirror must first reflect light to the combiner and then transmit light from the combiner to the eye of the user.
  • the loss of light associated with the fold mirror critically decreases the intensity of the image light transmitted to the eye position of the user.
  • a fold mirror with a dielectric or holographic dichromated gelatin coating will reflect a maximum amount (and, consequently, transmit a minimum amount) of linearly polarized light when the E vector, representing the electric field associated with a light wave, is oscillating in a plane that is perpendicular to the plane of incidence of the light with the fold mirror (termed “S polarization”) .
  • S polarization the plane of incidence of the light with the fold mirror
  • Such a fold mirror will transmit a maximum amount (and, accordingly, reflect a minimum amount) of linearly polarized light when the E vector is oscillating in the plane of incidence of the light with the fold mirror (termed "P polarization”) .
  • one or more wave plates can be inserted in the optical path of a folded catadioptric display to rotate the E vector such that the light reaching the fold mirror from the image generator is S polarized while the light arriving at the fold mirror from the combiner is P polarized.
  • the amount of light from the image generator that reaches the eye position of the user is substantially increased.
  • a fiber optic faceplate depolarizes light to the extent that if all the light entering the faceplate is linearly polarized, only two-thirds of the light exiting the faceplate is so polarized, it is preferable to utilize this technique with a folded catadioptric display that incorporates no faceplate.
  • Figure 1 shows the intensified visual display that is utilized when the image generator produces S polarized image light.
  • FIG 2 portrays the same intensified visual display as Figure 1 with the exception that the wave plate is attached to the reflective combiner.
  • Figure 3 illustrates the intensified visual display that is used when the image generator produces P polarized image light.
  • Figure 4 depicts an intensified visual display which differs from the display of Figure 3 only in that the second quarter-wave plate is laminated to the fold mirror.
  • the user-mounted display comprises, as depicted in Figure 1, a fold mirror (1) located to receive the S polarized image light from an image generator (2) and to reflect such S polarized image light; a quarter-wave plate (3) positioned so that the S polarized image light reflected from the fold mirror (1) is transmitted through said quarter-wave plate (3) and retarded by one-quarter wave in order to exit the quarter-wave plate (3) as circularly polarized image light; and a reflective combiner (4) situated to receive the circularly polarized image light from the quarter-wave plate (3) , reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through said reflective combiner (4) from the surrounding environment, and transmit the combined environmental light rays and circularly polarized image light through the quarter-wave plate (3), which again retards the circularly polarized image light by one-quarter wave so that it exits the quarter-wave plate (3) as P
  • the optical path (6) of the image light is displayed in Figure 1.
  • the handedness of the circularly polarized light is inverted, i.e., changed from left to right or from right to left .
  • the quarter-wave plate (3) is, as shown in Figure 2, attached to the reflective combiner (4) .
  • quarter-wave plate (3) The precise nature of the quarter-wave plate (3) is not critical. It is, however, preferable to employ a single-order plate so that dependence on angle and wavelength is minimized.
  • Quarter-wave plates are made from plastics and crystals or constructed holographically.
  • a holographic wave plate is simply a high-frequency plane grating; the frequency is selected to be sufficiently high that the grating will not diffract light at any angle within the range of angles at which light may strike the grating in the intensified visual display.
  • a plastic wave plate is, however, more dispersive, and has lower optical properties, than a crystalline or holographic wave plate.
  • the user-mounted display comprises, as shown in Figure 3, a first quarter-wave plate (31) located so that the P polarized image light from an image generator (2) is transmitted through said first quarter-wave plate (31) and retarded by one-quarter wave in order to exit the first quarter-wave plate
  • a fold mirror (1) situated to receive the S polarized image light from the second quarter-wave plate (32) and to reflect such S polarized image light through the second quarter- wave plate (32) where the S polarized image light will again be retarded by one-quarter wave and, consequently, exit said second quarter-wave plate (32) as circularly polarized image light; and a reflective combiner (4) placed to receive the circularly polarized image light from the second quarter-wave plate (32) , reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through the combiner (4) from the surrounding environment, and transmit the combined environmental light rays and circularly polarized image light through the second quarter-wave plate (32) , which again retards the circularly polarized image light by one-quarter wave so that it exits the second quarter-wave plate (32) as P polarized image light which then passes through the fold mirror (1) with the environmental light rays and subsequently reaches the eye position (5) of the user,
  • the handedness of the circularly polarized light is inverted, i.e., changed from left to right or from right to left.
  • the second quarter-wave plate (32) can optionally be laminated to the fold mirror (1) , as portrayed in Figure 4. This has the advantage of reducing the number of components which must be optically aligned. Additionally, it creates fewer surfaces on which an anti-reflective coating must be placed.
  • intensified visual display is made.
  • Industrial uses of the intensified visual display include, but are not necessarily limited to, providing a heads-up display or helmet-mounted display which enables a pilot or driver of a ground vehicle, such as military tank, to receive visual information about the pilot's plane or the driver's vehicle without looking away from the surrounding outside environment.

Abstract

The intensified visual display relates to visual displays which combine generated images with the view of the environment surrounding a user and transmit such combined visual information to the eye position of the user. A fold mirror (1) frequently utilized in such displays reflects only a fraction of the light striking it and, similarly, transmits only a different fraction of the light reaching it. The fold mirror (1) will reflect a maximum amount of light when such light is S polarized and transmit a maximum amount of light when the light is P polarized. If the image generator produces S polarized light, one quarter-wave plate (3) is used to assure that image light to be reflected by the fold mirror (1) is S polarized while image light to be transmitted through the fold mirror (1) is P polarized. If the image generator produces P polarized light, a first quarter-wave plate (31) and a second quarter-wave plate (32) are employed.

Description

DESCRIPTION INTENSIFIED VISUAL DISPLAY
TECHNICAL FIELD This invention relates to visual display which combine generated images with the view of the environment surrounding a user and transmit such combined visual information to the eye position of the user.
BACKGROUND ART
It is often desirable to provide visual information to a living being, usually a person.
Frequently one wishes to superimpose such visual information upon the being's view of the real world.
Such a display requires, in a form known as a folded catadioptric display, an image generator; a beam splitter, which receives the image light from the image generator and sends a fraction, designated the reflected fraction, of such image light to a reflective combiner that both allows light from the real world to pass through such combiner and reflects the image light such that both the real-world light and the image light are transmitted to the eye of the user through the beam splitter.
The beam splitter will transmit a fraction, designated the transmitted fraction, of the image light reflected from the collimator-combiner. Of course, only a fraction of the real-world light is also transmitted by the beam splitter; but attention is directed only to the image light since it is image light that tends to be critically low in intensity.
To correct for aberrations and distortions produced by the beam splitter and the combiner, a correction lens is often placed in the optical path between the image generator and the beam splitter.
The light emitted from liquid crystal displays is linearly polarized because liquid crystal displays utilize polarizers to modulate amplitude. The only cathode ray tubes which produce linearly polarized light are those which are colored with an active wave plate, such as the Tektronics Pi cell, all of the light from which is linearly polarized.
When a fold mirror is selected as the beam splitter, it is plastic or glass having, preferably, a dielectric or holographic dichromated gelatin coating. Metal coatings are unacceptable because the fold mirror must first reflect light to the combiner and then transmit light from the combiner to the eye of the user.
DISCLOSURE OF INVENTION
As mentioned above, the loss of light associated with the fold mirror critically decreases the intensity of the image light transmitted to the eye position of the user.
The principal inventive concept associated with the present invention is the recognition of three facts : A fold mirror with a dielectric or holographic dichromated gelatin coating will reflect a maximum amount (and, consequently, transmit a minimum amount) of linearly polarized light when the E vector, representing the electric field associated with a light wave, is oscillating in a plane that is perpendicular to the plane of incidence of the light with the fold mirror (termed "S polarization") . Such a fold mirror will transmit a maximum amount (and, accordingly, reflect a minimum amount) of linearly polarized light when the E vector is oscillating in the plane of incidence of the light with the fold mirror (termed "P polarization") . And one or more wave plates can be inserted in the optical path of a folded catadioptric display to rotate the E vector such that the light reaching the fold mirror from the image generator is S polarized while the light arriving at the fold mirror from the combiner is P polarized.
When this is done, the amount of light from the image generator that reaches the eye position of the user is substantially increased.
Since a fiber optic faceplate depolarizes light to the extent that if all the light entering the faceplate is linearly polarized, only two-thirds of the light exiting the faceplate is so polarized, it is preferable to utilize this technique with a folded catadioptric display that incorporates no faceplate.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 shows the intensified visual display that is utilized when the image generator produces S polarized image light.
Figure 2 portrays the same intensified visual display as Figure 1 with the exception that the wave plate is attached to the reflective combiner.
Figure 3 illustrates the intensified visual display that is used when the image generator produces P polarized image light.
Figure 4 depicts an intensified visual display which differs from the display of Figure 3 only in that the second quarter-wave plate is laminated to the fold mirror.
BEST MODE FOR CARRYING OUT THE INVENTION If the light from the image generator is S polarized, the user-mounted display comprises, as depicted in Figure 1, a fold mirror (1) located to receive the S polarized image light from an image generator (2) and to reflect such S polarized image light; a quarter-wave plate (3) positioned so that the S polarized image light reflected from the fold mirror (1) is transmitted through said quarter-wave plate (3) and retarded by one-quarter wave in order to exit the quarter-wave plate (3) as circularly polarized image light; and a reflective combiner (4) situated to receive the circularly polarized image light from the quarter-wave plate (3) , reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through said reflective combiner (4) from the surrounding environment, and transmit the combined environmental light rays and circularly polarized image light through the quarter-wave plate (3), which again retards the circularly polarized image light by one-quarter wave so that it exits the quarter-wave plate (3) as P polarized light which then passes through the fold mirror (1) with the environmental light rays and subsequently reaches the eye position (5) of the user, as also do the environmental light rays with which the image light has been combined.
The optical path (6) of the image light is displayed in Figure 1.
When the circularly polarized image light is reflected by the combiner (4) , the handedness of the circularly polarized light is inverted, i.e., changed from left to right or from right to left . Optionally, the quarter-wave plate (3) is, as shown in Figure 2, attached to the reflective combiner (4) .
The precise nature of the quarter-wave plate (3) is not critical. It is, however, preferable to employ a single-order plate so that dependence on angle and wavelength is minimized.
Quarter-wave plates are made from plastics and crystals or constructed holographically. A holographic wave plate is simply a high-frequency plane grating; the frequency is selected to be sufficiently high that the grating will not diffract light at any angle within the range of angles at which light may strike the grating in the intensified visual display. A plastic wave plate is, however, more dispersive, and has lower optical properties, than a crystalline or holographic wave plate.
If the light from the image generator is P polarized, the user-mounted display comprises, as shown in Figure 3, a first quarter-wave plate (31) located so that the P polarized image light from an image generator (2) is transmitted through said first quarter-wave plate (31) and retarded by one-quarter wave in order to exit the first quarter-wave plate
(31) as circularly polarized image light; a second quarter-wave plate (32) positioned so that the circularly polarized image light from the first quarter-wave plate is transmitted through said second quarter-wave plate (32) and retarded by one-quarter wave in order to exit the second quarter-wave plate
(32) as S polarized image light; a fold mirror (1) situated to receive the S polarized image light from the second quarter-wave plate (32) and to reflect such S polarized image light through the second quarter- wave plate (32) where the S polarized image light will again be retarded by one-quarter wave and, consequently, exit said second quarter-wave plate (32) as circularly polarized image light; and a reflective combiner (4) placed to receive the circularly polarized image light from the second quarter-wave plate (32) , reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through the combiner (4) from the surrounding environment, and transmit the combined environmental light rays and circularly polarized image light through the second quarter-wave plate (32) , which again retards the circularly polarized image light by one-quarter wave so that it exits the second quarter-wave plate (32) as P polarized image light which then passes through the fold mirror (1) with the environmental light rays and subsequently reaches the eye position (5) of the user, as also do the environmental light rays with which the image light has been combined. The optical path (6) of the image light is depicted in Figure 3.
Again, when the circularly polarized image light is reflected by the combiner (4) , the handedness of the circularly polarized light is inverted, i.e., changed from left to right or from right to left.
The second quarter-wave plate (32) can optionally be laminated to the fold mirror (1) , as portrayed in Figure 4. This has the advantage of reducing the number of components which must be optically aligned. Additionally, it creates fewer surfaces on which an anti-reflective coating must be placed.
INDUSTRIAL APPLICABILITY
From the preceding it is obvious how the intensified visual display is made. Industrial uses of the intensified visual display include, but are not necessarily limited to, providing a heads-up display or helmet-mounted display which enables a pilot or driver of a ground vehicle, such as military tank, to receive visual information about the pilot's plane or the driver's vehicle without looking away from the surrounding outside environment.

Claims

1. An intensified visual display for use with an image generator that produces S polarized light, which comprises:
a fold mirror located to receive S polarized image light from an image generator and to reflect such S polarized image light;
a quarter-wave plate positioned so that the S polarized image light reflected from the fold mirror is transmitted through said quarter-wave plate and retarded by one-quarter wave in order to exit the quarter-wave plate as circularly polarized image light; and
a reflective combiner situated to receive the circularly polarized image light from the quarter-wave plate, reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through said reflective combiner from the surrounding environmental, and transmit the combined environmental light rays and circularly polarized image light through the quarter-wave plate, which again retards the circularly polarized image light by one-quarter wave so that it exits the quarter-wave plate as P polarized image light which then passes through the fold, mirror with the environmental light rays and subsequently reaches the eye position of the user, as also do the environmental light rays with which the image light has been combined.
2. The intensified visual display as recited in claim 1, wherein: the quarter-wave plate is attached to the reflective combiner.
3. An intensified visual display for use with an image generator that produces P polarized light, which comprises :
a first quarter-wave plate located so that the P polarized image light from an image generator is transmitted through said first quarter-wave plate and retarded by one-quarter wave in order to exit the first quarter-wave plate as circularly polarized image light;
a second quarter-wave plate positioned so that the circularly polarized image light from the first quarter-wave plate is transmitted through said second quarter-wave plate and retarded by one-quarter wave in order to exit the second quarter-wave plate as S polarized image light;
a fold mirror situated to receive the S polarized image light from the second quarter- wave plate and to reflect such S polarized image light through the second quarter-wave plate where the S polarized image light will again be retarded by one quarter-wave and, consequently, exit said second quarter-wave plate as circularly polarized image light; and
a reflective combiner placed to receive the circularly polarized image light from the second quarter-wave plate, reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through the reflective combiner from the surrounding environment, and transmit the combined environmental light rays and circularly polarized image light through the second quarter-wave plate, which again retards the circularly polarized image light by one-quarter wave so that it exits the second quarter-wave plate as P polarized image light which then passes through the fold mirror with the environmental light rays and subsequently reaches the eye position of the user, as also do the environmental light rays with which the image light has been combined.
4. The intensified visual display as recited in claim 3, wherein:
the second quarter-wave plate is laminated to the fold mirror.
5. A process for intensifying the image light transmitted to the eye position of the user of a visual display when the image light produced by the image generator with which the process is used is S polarized, which comprises:
locating a fold mirror to receive S polarized image light from the image generator and to reflect such S polarized image light;
positioning a quarter-wave plate so that the S polarized image light reflected from the fold mirror is transmitted through said quarter- wave plate and retarded by one-quarter wave in order to exit the quarter-wave plate as circularly polarized image light; and situating a reflective combiner to receive the circularly polarized image light from the quarter-wave plate, reflect such circularly polarized image light, combine such circularly polarized image light with light rays transmitted through said reflective combiner from the surrounding environmental, and transmit the combined environmental light rays and circularly polarized image light through the quarter-wave plate, which again retards the circularly polarized image light by one-quarter wave so that it exits the quarter-wave plate as P polarized image light which then passes through the fold mirror with the environmental light rays and subsequently reaches the eye position of the user, as also do the environmental light rays with which the image light has been combined.
6. The process for intensifying the image light transmitted to the eye position of the user of a visual display when the image light produced by the image generator with which the process is used is S polarized, as recited in claim 5, further comprising:
attaching the quarter-wave plate to the reflective combiner.
7. A process for intensifying the image light transmitted to the eye position of the user of a visual display when the image light produced by the image generator with which the process is used is P polarized, which comprises:
locating a first quarter-wave plate so that the P polarized image light from an image generator is transmitted through said first quarter-wave plate and retarded by one-quarter wave in order to exit the first quarter-wave plate as circularly polarized image light;
5 positioning a second quarter-wave plate so that the circularly polarized image light from the first quarter-wave plate is transmitted through said second quarter-wave plate and retarded by one-quarter wave in order to exit 10 the second quarter-wave plate as S polarized image light;
situating a fold mirror to receive the S polarized image light from the second quarter-
15 wave plate and to reflect such S polarized image light through the second quarter-wave plate where the S polarized image light will again be retarded by one quarter-wave and, consequently, exit said second quarter-wave plate as
20 circularly polarized image light; and
placing a reflective combiner to receive the circularly polarized image light from the second quarter-wave plate, reflect such
25 circularly polarized image light, combine such circularly polarized image light with light rays transmitted through the reflective combiner from the surrounding environment, and transmit the combined environmental light rays and circularly
30 polarized image light through the second quarter-wave plate, which again retards the circularly polarized image light by one-quarter wave so that it exits the second quarter-wave plate as P polarized image light which then
35 passes through the fold mirror with the environmental light rays and subsequently reaches the eye position of the user, as also do the environmental light rays with which the image light has been combined.
8. The process for intensifying the image light transmitted to the eye position of the user of a visual display when the image light produced by the image generator with which the process is used is P polarized, as recited in claim 7, further comprising:
laminating the second quarter-wave plate to the fold mirror.
EP94922412A 1994-02-07 1994-02-07 Intensified visual display Withdrawn EP0746782A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US1994/001391 WO1995021391A1 (en) 1994-02-07 1994-02-07 Intensified visual display

Publications (2)

Publication Number Publication Date
EP0746782A1 true EP0746782A1 (en) 1996-12-11
EP0746782A4 EP0746782A4 (en) 1997-01-15

Family

ID=22242255

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94922412A Withdrawn EP0746782A1 (en) 1994-02-07 1994-02-07 Intensified visual display

Country Status (4)

Country Link
EP (1) EP0746782A1 (en)
JP (1) JPH09508477A (en)
AU (1) AU7352994A (en)
WO (1) WO1995021391A1 (en)

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09508711A (en) * 1994-02-07 1997-09-02 バーチュアル・アイ／オゥ・インコーポレイテッド Personal visual display system
FR2759788B1 (en) * 1997-02-14 1999-05-07 Sextant Avionique REDUCTION OF INTERFERENCE IMAGES IN A HIGH HEAD VIEWFINDER
JPH11237584A (en) * 1997-12-19 1999-08-31 Sharp Corp Picture display device, head-mount type display using the picture display device, and video communication equipment
FR2780519B1 (en) * 1998-06-26 2001-11-30 Thomson Csf COLLIMATION DEVICE WITH IMPROVED TRANSMISSION COEFFICIENT
JP4341108B2 (en) * 1999-07-14 2009-10-07 ソニー株式会社 Virtual image observation optical device
US6522474B2 (en) * 2001-06-11 2003-02-18 Eastman Kodak Company Head-mounted optical apparatus for stereoscopic display
CA2916484C (en) 2013-06-26 2021-11-02 Bae Systems Plc Display comprising an optical waveguide for displaying an image
GB2515520B (en) * 2013-06-26 2017-10-04 Bae Systems Plc Improvements in and relating to displays
CN107003526A (en) * 2015-03-19 2017-08-01 松下知识产权经营株式会社 Head-up display
WO2017179110A1 (en) * 2016-04-11 2017-10-19 カラーリンク・ジャパン 株式会社 Projection device, projection system, and spectacle type display device
JP6572856B2 (en) 2016-09-22 2019-09-11 株式会社デンソー Head-up display device
WO2018169018A1 (en) * 2017-03-17 2018-09-20 富士フイルム株式会社 Image display system
JP7069862B2 (en) * 2018-03-12 2022-05-18 株式会社Ｊｖｃケンウッド Image display device
US11573357B2 (en) * 2019-12-04 2023-02-07 Meta Platforms Technologies, Llc Lens assembly having circular reflective polarizer
CN111221130B (en) * 2020-03-20 2022-03-04 维沃移动通信有限公司 Optical system and near-eye display apparatus
CN111273449A (en) * 2020-03-23 2020-06-12 深圳惠牛科技有限公司 Augmented reality system and augmented reality device
CN111367085A (en) * 2020-04-30 2020-07-03 宁波鸿蚁光电科技有限公司 Optical display system with folding light path and AR equipment
JP7002021B2 (en) 2020-05-12 2022-01-20 パナソニックＩｐマネジメント株式会社 Display device
JP7113239B2 (en) * 2020-07-03 2022-08-05 パナソニックＩｐマネジメント株式会社 display system
CN113885206A (en) * 2021-10-08 2022-01-04 小派科技（上海）有限责任公司 Optical module, optical module system, display device, head-mounted display equipment and system thereof
WO2024038589A1 (en) * 2022-08-19 2024-02-22 日本電信電話株式会社 Aerial image display device and display method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4630040A (en) * 1983-03-31 1986-12-16 Motorola, Inc. Variable color electrooptic display
US4653875A (en) * 1984-11-02 1987-03-31 Hines Stephen P Infinity display apparatus using cylindrical beam-splitters
US4973132A (en) * 1989-10-27 1990-11-27 Hughes Aircraft Company Polarized holographic heads up display
EP0566004A2 (en) * 1992-04-07 1993-10-20 Hughes Aircraft Company Virtual image display having a high efficiency grid beamsplitter
FR2690534A1 (en) * 1992-04-24 1993-10-29 Thomson Csf Optical collimator, especially for helmet with visor - incorporates circular polarisation selector followed by semi-reflective spherical mirror and linear reflective polariser

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4961625A (en) * 1987-09-18 1990-10-09 Flight Dynamics, Inc. Automobile head-up display system with reflective aspheric surface
US5231379A (en) * 1987-09-18 1993-07-27 Hughes Flight Dynamics, Inc. Automobile head-up display system with apparatus for positioning source information
US5053755A (en) * 1989-05-18 1991-10-01 Hughes Aircraft Company Automotive head-up display with high brightness in daytime and high contrast in nighttime
US5198928A (en) * 1991-06-26 1993-03-30 Hughes Aircraft Company Light weight binocular helmet visor display

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4630040A (en) * 1983-03-31 1986-12-16 Motorola, Inc. Variable color electrooptic display
US4653875A (en) * 1984-11-02 1987-03-31 Hines Stephen P Infinity display apparatus using cylindrical beam-splitters
US4973132A (en) * 1989-10-27 1990-11-27 Hughes Aircraft Company Polarized holographic heads up display
EP0566004A2 (en) * 1992-04-07 1993-10-20 Hughes Aircraft Company Virtual image display having a high efficiency grid beamsplitter
FR2690534A1 (en) * 1992-04-24 1993-10-29 Thomson Csf Optical collimator, especially for helmet with visor - incorporates circular polarisation selector followed by semi-reflective spherical mirror and linear reflective polariser

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of WO9521391A1 *

Also Published As

Publication number Publication date
WO1995021391A1 (en) 1995-08-10
JPH09508477A (en) 1997-08-26
AU7352994A (en) 1995-08-21
EP0746782A4 (en) 1997-01-15

Similar Documents

Publication Publication Date Title
US5903396A (en) Intensified visual display
WO1995021391A1 (en) Intensified visual display
US6075651A (en) Compact collimating apparatus
JP3105534B2 (en) Helmet mounted display
US5408346A (en) Optical collimating device employing cholesteric liquid crystal and a non-transmissive reflector
US10746989B2 (en) Micro collimator system and method for a head up display (HUD)
EP0834097B1 (en) Head gear display system
US9523852B1 (en) Micro collimator system and method for a head up display (HUD)
US4859031A (en) Optical collimating apparatus
US9013793B2 (en) Lightweight eyepiece for head mounted display
US20070273970A1 (en) Wide field of view, compact collimating apparatus
US7482996B2 (en) Head-up display
US5715023A (en) Plane parallel optical collimating device employing a cholesteric liquid crystal
JPH0643397A (en) Virtual image display with high-efficiency grid beam divider
JPH02132411A (en) Optical combiner collimator apparatus
CA2017251A1 (en) Optical device enabling the introduction of a collimated image in an observer's field of vision
WO2003100517A2 (en) Real image configuration for a high efficiency heads-up display (hud) using a polarizing mirror and a polarization preserving screen
WO1995021396A2 (en) Personal visual display
CN108983423A (en) A kind of Binocular displays system and vehicle-mounted head-up-display system
US5984477A (en) Helmet mounted display with improved SLM illumination
EP0296710B1 (en) Head-up display combiner utilizing a cholesteric liquid crystal element
CN114660807A (en) Near-to-eye display device
US20230145899A1 (en) Optical apparatus and near-eye display device
CN115877560B (en) Laser scanning imaging module, device and AR display equipment
CN108333776B (en) Near-eye display optical module and near-eye display system

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19960906

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

A4 Supplementary search report drawn up and despatched

Effective date: 19961126

AK Designated contracting states

Kind code of ref document: A4

Designated state(s): DE FR GB

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 19970509