Image display apparatus

• US 6,771,403 B1
• Filed: 04/24/2003
• Issued: 08/03/2004
• Est. Priority Date: 01/22/2003
• Status: Active Grant

• Current Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Original Assignee: Minolta Corporation Limited (Konica Minolta Inc.)
• Inventors: Endo, Takeshi, Morimoto, Takashi, Kasai, Ichiro, Noda, Tetsuya
• Primary Examiner(s): Juba, Jr., John
• Application Number:
  US10/422,249
• Publication Number:
  US 20040141217A1
• Time in Patent Office: 467 Days
• Field of Search: 359/13, 359/14, 359/15, 345/7, 345/8, 345/9
• US Class Current: 359/13
• CPC Class Codes: G02B 2027/0174 holographic
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/203 having holographic or diffractive elements diffraction gratings per se G02B5/18; holographic elements per se G02B5/32; generating the spectrum using diffraction elements G01J3/18
• CPC Class Codes: G02B 5/32 Holograms used as optical elements
• CPC Class Codes: G03H 1/0408 Total internal reflection [TIR] holograms, e.g. edge lit or substrate mode holograms
• CPC Class Codes: G03H 2270/55 being an optical element, e.g. spectacles

Abstract

A holographic element is a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate. The holographic element forms, out of image light having a predetermined wavelength width emanating from an image display element, a plurality of observation pupils at spatially different locations, and acts in such a way as to fulfill prescribed conditions for an identical incident ray over the entire area in which the image light is incident on the holographic element.

Claims

1. A holographic element that is a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate, the holographic element forming, out of image light having a predetermined wavelength width emanating from an image display element, a plurality of observation pupils at spatially different locations,

wherein the holographic element acts in such a way as to fulfill the following conditional formulae (I) and (II) for an identical incident ray over an entire area in which the image light is incident on the holographic element:

2. A holographic element as claimed in claim 1,

wherein the composite hologram constituting the holographic element is a multiple-layer hologram fabricated by laying on one another a plurality of holograms each having a pattern of interference fringes recorded thereon.

3. A holographic element as claimed in claim 1,

wherein the composite hologram constituting the holographic element is a, multiple-exposure hologram fabricated by recording a plurality of patterns of interference fringes on a single photosensitive material by multiple exposure.

4. A holographic element as claimed in claim 1,

wherein the holographic element has a nonaxisymmetric optical power.

5. A holographic clement as claimed in claim 1,

wherein the holographic element has a plurality of diffraction wavelength peaks.

6. A holographic element as claimed in claim 1,

wherein the composite hologram constituting the holographic element is formed by using photopolymer as a photosensitive material.

7. An image display apparatus comprising:

an image display element for displaying a two-dimensional image;

an enlargement optical system for projecting, with enlargement, the image displayed on the image display element; and

a holographic element included in the enlargement optical system, the holographic element being a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate, the holographic element forming, out of image light having a predetermined wavelength width emanating from the image display element, a plurality of observation pupils at spatially different locations,

wherein the holographic element acts in such a way as to fulfill the following conditional formulae (I) and (II) for an identical incident ray over an entire area in which the image light is incident on the holographic element;

8. An image display apparatus as claimed in claim 7,

wherein the composite hologram constituting the holographic element is a multiple-layer hologram fabricated by laying on one another a plurality of holograms each having a pattern of interference fringes recorded thereon.

9. An image display apparatus as claimed in claim 7,

wherein the composite hologram constituting the holographic element is a multiple-exposure hologram fabricated by recording a plurality of patterns of interference fringes on a single photosensitive material by multiple exposure.

10. An image display apparatus as claimed in claim 7,

wherein the holographic element has a nonaxisymmetric optical power.

11. An image display apparatus as claimed in claim 7,

wherein the holographic element has a plurality of diffraction wavelength peaks.

12. An image display apparatus as claimed in claim 7,

wherein the composite hologram constituting the holographic element is formed by using photopolymer as a photosensitive material.

13. An image display apparatus comprising:

an image display element for displaying a two-dimensional image,

an enlargement optical system for reflecting, as a first image, the image displayed on the image display element so as to project, with enlargement, the first image onto an observer'"'"'s pupil while transmitting, as a second image, an image from an outside world so as to direct the second image to the observer'"'"'s pupil; and

a holographic element included in the enlargement optical system, the holographic element being a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate, the holographic element forming, out of image light having a predetermined wavelength width emanating from the image display element, a plurality of observation pupils at spatially different locations,

wherein the holographic element acts in such a way as to fulfill the following conditional formulae (I) and (II) for an identical incident ray over an entire area in which the image light is incident on the holographic element;

14. An image display apparatus as claimed in claim 13,

wherein the composite hologram constituting the holographic element is a multiple-layer hologram fabricated by laying on one another a plurality of holograms each having a pattern of interference fringes recorded thereon.

15. An image display apparatus as claimed in claim 13,

wherein the composite hologram constituting the holographic element is a multiple-exposure hologram fabricated by recording a plurality of patterns of interference fringes on a single photosensitive material by multiple exposure.