EP0444215A1
Expired / Lapsed
EP
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Achromatic hologram optical system
Assignee: Fujitsu Ltd
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Filing: 1990-09-19
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Granted: —
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Expires: 2010-09-19
Abstract
Abstract The achromatic hologram optical system transforms a wave surface A into another wave surface B characterised in that two holograms (H1, H2) are provided. An optical path length from the cophasal surface of the wave surface A to that of the wave surface B is constant, and surface configurations of the two holograms are curved surfaces. @(56pp Dwg.No.0/24).
Inventors
- 👤 Fumio Yamagishi
- 👤 Satoshi Maeda
- 👤 Hiroyuki Ikeda
- 👤 Masayuki Kato
- 👤 Hirokazu Aritake
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 03:34
CPC Classifications
G; G03; G03H; G03H1/00; G02; G02B; G02B5/00; G02B5/32; G03H1/26; G03H2001/2605; G03H2001/261; G03H2270/00; G03H2270/20; G03H2270/21
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
57 words
An achromatic hologram optical system having two holograms for converting a wave front A into a wave front B, wherein the length of an optical path from an equiphase front of the wave front A to an equiphase front of the wave front B is constant, and each of the two holograms has a curved surface shape.
Claim 2
Dependent Claim
57 words
An achromatic hologram optical system having two holograms for converting a wave front A into a wave front B, wherein the length of an optical path from an equiphase front of the wave front A to an equiphase front of the wave front B is constant, and each of the two holograms has a curved surface shape.
Claim 3
Dependent Claim
60 words
An achromatic hologram optical system having two holograms for converting a wave front A into a wave front B, wherein the length of an optical path from an equiphase front of the wave front A to an equiphase front of the wave front B is constant, and the two holograms are joined with a divergent wave or a convergent wave.
Claim 4
Dependent Claim
60 words
An achromatic hologram optical system having two holograms for converting a wave front A into a wave front B, wherein the length of an optical path from an equiphase front of the wave front A to an equiphase front of the wave front B is constant, and the two holograms are joined with a divergent wave or a convergent wave.
Claim 5
Dependent Claim
133 words
A hologram optical system as set forth in claim 1 or 2, wherein the two holograms are inclined by τ with respect to each other, the first hologram converts a divergent spherical wave into another divergent spherical wave, the second hologram converts a divergent spherical wave into another divergent spherical wave, and the following relationships are established: where β is an angle of an incident optical axis to the first hologram, δ an angle of an outgoing optical axis from the first hologram, a an angle of an outgoing optical axis from the second hologram, ℓ 4 a distance on an optical axis from the first hologram to the second hologram, and 1 3 a distance from a light source of the spherical wave that enters the second hologram to the second hologram.
Claim 6
Dependent Claim
71 words
A hologram optical system as set forth in claim 3 further satisfying the following relationships: where 1 2 is a distance on an optical axis from a light point of the divergent spherical wave that enters the first hologram to the first hologram, and ℓ 1 a distance on an optical axis from a light point of the divergent spherical wave comes out of the second hologram to the second hologram.
Claim 7
Dependent Claim
132 words
A hologram optical system as set forth in claim 1 or 2, wherein the two holograms are inclined by T with respect to each other, the first hologram converts a divergent spherical wave into another divergent spherical wave, the second hologram converts a divergent spherical wave into a convergent spherical wave, and the following relationships are established: where is an angle of an incident optical axis to the first hologram, δ an angle of an outgoing optical axis from the first hologram, a an angle of an outgoing optical axis from the second hologram, ℓ 4 a distance on an optical axis from the first hologram to the second hologram, and 1 3 a distance from a light source of the spherical wave that enters the second hologram to the second hologram.
Claim 8
Dependent Claim
70 words
A hologram optical system as set forth in claim 5 further satisfying the following relationships: where t 2 is a distance on an optical axis from a light point of the divergent spherical wave that enters the first hologram to the first hologram, and ℓ 1 a distance of a light point of the divergent spherical wave emitted from the second hologram, from the second hologram, on an optical axis.
Claim 9
Dependent Claim
133 words
A hologram optical system as set forth in claim 1 or 2, wherein the two holograms are inclined by y with respect to each other, the first hologram converts a convergent spherical wave into a divergent spherical wave, the second hologram converts a divergent spherical wave into another divergent spherical wave, and the following relationships are established: where β is an angle of an incident optical axis to the first hologram, 8 an angle of an outgoing optical axis from the first hologram, α an angle of an outgoing optical axis from the second hologram, ℓ 4 a distance on an optical axis from the first hologram to the second hologram, and ℓ 3 a distance from a light source of the spherical wave that enters the second hologram to the second hologram.
Claim 10
Dependent Claim
70 words
A hologram optical system as set forth in claim 7 further satisfying the following relationships: where t 2 is a distance on an optical axis from a light point of the divergent spherical wave that enters the first hologram to the first hologram, and ℓ 1 a distance of a light point of the divergent spherical wave emitted from the second hologram, from the second hologram, on an optical axis.
Claim 11
Dependent Claim
132 words
A hologram optical system as set forth in claim 1 or 2, wherein the two holograms are inclined by y with respect to each other, the first hologram converts a divergent spherical wave into a convergent spherical wave, the second hologram converts a convergent spherical wave into a divergent spherical wave, and the following relationships are established: where is an angle of an incident optical axis to the first hologram, 8 an angle of an outgoing optical axis from the first hologram, a the angle of an outgoing optical axis of the second hologram, ℓ 4 a distance on an optical axis from the first hologram to the second hologram, and ℓ 3 a distance of a light source of the spherical wave incident upon the second hologram from the second hologram.
Claim 12
Dependent Claim
70 words
A hologram optical system as set forth in claim 9 further satisfying the following relationships: where 1 2 is a distance on an optical axis from a light point of the divergent spherical wave that enters the first hologram to the first hologram, and 1 1 a distance of a light point of the divergent spherical wave emitted from the second hologram, from the second hologram, on an optical axis.
Claim 13
Dependent Claim
28 words
A hologram optical system as set forth in any one of claims 3 to 10, wherein each of the first and second holograms is a reflection type hologram.
Claim 14
Dependent Claim
28 words
A hologram optical system as set forth in any one of claims 3 to 10, wherein each of the first and second holograms is a transmission type hologram.
Claim 15
Dependent Claim
36 words
A hologram optical system as set forth in any one of claims 3 to 10, wherein one of the first and second holograms is a transmission type hologram, and the other is a reflection type hologram.
Claim 16
Dependent Claim
28 words
A hologram optical system as set forth in claim 3 applied for a video display unit having a light source for emitting information light to the first hologram.
Claim 17
Dependent Claim
47 words
An achromatic hologram optical system for converting a wave front A into a wave front B, having at least three holograms, the length of an optical path from an equiphase front of the wave front A to an equiphase front of the wave front B being constant.
Claim 18
Dependent Claim
47 words
An achromatic hologram optical system for converting a wave front A into a wave front B, having at least three holograms, the length of an optical path from an equiphase front of the wave front A to an equiphase front of the wave front B being constant.
Claim 19
Dependent Claim
43 words
An achromatic hologram optical system as set forth in claim 15, which is a coaxial optical system for converting a divergent spherical wave into a convergent spherical wave, in which a spatial frequency of each of the holograms decreases in a radial direction.
Claim 20
Dependent Claim
44 words
A hologram optical system as set forth in claim 15, wherein an angle formed between the first and second holograms is equal to an angle formed between the second and third holograms, and the first and third holograms are in parallel with each other.
Claim 21
Dependent Claim
28 words
A hologram optical system as set forth in claim 17, wherein an incident beam and an outgoing beam are plane waves that are in parallel with each other.
References Cited (Backward Citations)
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