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US4856869A Expired / Lapsed US ⏱️ 0.0 years remaining

Display element and observation apparatus having the same

Assignee: Canon Inc
•
Filing: 1987-04-06
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Granted: 1989-08-15
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Expires: 2007-04-06
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Abstract

Abstract A display element includes a substrate and a display pattern formed on the substrate, the display pattern including a diffraction grating. The width in the direction perpendicular to the grating lines of the diffraction grating of the display pattern is selected so as to prevent re-diffraction of the light diffracted by the one diffraction grating. An observation apparatus includes the afore-said display element, but the display pattern has a first diffraction grating structure and a second diffraction grating structure. An illuminating system and an observation system are added so as to allow for observation of the display pattern. The direction of the grating lines of the first diffraction grating structure differs from that of the grating lines of the second diffraction grating structure, thereby preventing the occurrence of a rainbow-like image.

Inventors

  • 👤 Hajime Sakata
  • 👤 Yasuyuki Watanabe
  • 👤 Masato Yamanobe
  • 👤 Yukitoshi Ohkubo
  • 👤 Akihiro Nagano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 03:07
CPC Classifications
G; G09; G09F; G09F9/00; G09F9/30; G09F9/35; G02; G02B; G02B5/00; G02B5/18; G02B5/1842; G02F; G02F1/00; G02F1/29; G02F1/292

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 50 words
A display element comprising: a substrate; and a display pattern formed on said substrate, said display pattern including a diffraction grating, wherein the width in the direction perpendicular to grating lines of said diffraction grating is selected so as to prevent rediffraction of the light diffracted by said diffraction grating.
Claim 2
Dependent Claim 50 words
A display element comprising: a substrate; and a display pattern formed on said substrate, said display pattern including a diffraction grating, wherein the width in the direction perpendicular to grating lines of said diffraction grating is selected so as to prevent rediffraction of the light diffracted by said diffraction grating.
Claim 3
Dependent Claim 40 words
A display element according to claim 1, wherein, when t represents the thickness of said substrate, n representing the refractive index of the same and w representing the width of said display pattern, w fulfills the following requirement: w<4×t×tan{sin.sup.-1 (1/n)}.
Claim 4
Dependent Claim 14 words
A display element according to claim 1, wherein said width w is: w<5 mm.
Claim 5
Dependent Claim 14 words
A display element according to claim 3, wherein said width w is: w<2 mm.
Claim 6
Dependent Claim 26 words
A display element according to claim 1, wherein the direction of said grating lines is inclined with respect to the longitudinal direction of said display pattern.
Claim 7
Dependent Claim 64 words
A display element according to claim 1, wherein said diffraction grating comprises: a relief pattern formed on said substrate, said relief pattern having a periodical grating portion; and a liquid crystal sealed in said grating portion of said relief pattern, said liquid crystal having a variable refractive index, and said display element further including means for controlling said refractive index of said liquid crystal.
Claim 8
Dependent Claim 196 words
An observation apparatus comprising: a display element including a substrate and first and second display patterns formed on said substrate, each of said display patterns having diffraction grating structures; an illuminating system, having a pupil, for supplying light to said display element; and an observation system, having a pupil, disposed to allow for observation of the first and second display patterns produced by the light diffracted by said diffraction grating structures, wherein letting in denote the angle of incidence of light with respect to said substrate, D 1 the diameter of said pupil of said illuminating system, D 0 the diameter of said pupil of said observation system, L i the distance between said substrate and the plane of said pupil of said illuminating system, L 0 the distance between said substrate and the plane of said pupil of said observation system, λ the wavelength of incident light, P the grating period of said diffraction grating structures of said first and second display patterns and n the refractive index of said substrate, the angle θ made by the grating lines of said diffraction grating structures of said first and second display patterns fulfills the requirement: ##EQU10##
Claim 9
Dependent Claim 196 words
An observation apparatus comprising: a display element including a substrate and first and second display patterns formed on said substrate, each of said display patterns having diffraction grating structures; an illuminating system, having a pupil, for supplying light to said display element; and an observation system, having a pupil, disposed to allow for observation of the first and second display patterns produced by the light diffracted by said diffraction grating structures, wherein letting in denote the angle of incidence of light with respect to said substrate, D 1 the diameter of said pupil of said illuminating system, D 0 the diameter of said pupil of said observation system, L i the distance between said substrate and the plane of said pupil of said illuminating system, L 0 the distance between said substrate and the plane of said pupil of said observation system, λ the wavelength of incident light, P the grating period of said diffraction grating structures of said first and second display patterns and n the refractive index of said substrate, the angle θ made by the grating lines of said diffraction grating structures of said first and second display patterns fulfills the requirement: ##EQU10##
Claim 10
Dependent Claim 65 words
An observation apparatus according to claim 7, wherein said diffraction grating structure comprise: a relief pattern formed on said substrate, said relief pattern having a periodical grating portion; and a liquid crystal sealed in said grating portion of said relief pattern, said liquid crystal having a variable refractive index, and said observation apparatus further including means for controlling said refractive index of said liquid crystal.
Claim 11
Dependent Claim 63 words
An observation apparatus according to claim 7, wherein said diffraction grating comprises: a relief pattern formed on said substrate, said relief pattern having a periodical grating portion; and a liquid crystal sealed in said grating portion of said relief pattern, said liquid crystal having a variable refractive index, and said display element having means for controlling said refractive index of said liquid crystal.
Claim 12
Dependent Claim 53 words
An observation apparatus according to claim 7, wherein said illuminating system is formed by an objective lens for forming an image of an object to be observed in the vicinity of said display element, and said first and second display patterns and the image of the object being observed by said observation system.
Claim 13
Dependent Claim 145 words
An observation apparatus comprising: a display element including a substrate and first and second display patterns formed on said substrate, each of said display patterns having diffraction grating structures; an illuminating system for supplying light to said display element; and an observation system disposed to allow for observation of the first and second display patterns produced by the light diffracted by said diffraction grating structure, wherein letting i denote the angle of incidence of light with respect to said substrate, λ the wavelength of incident light, P the grating period of said diffraction grating structures, K the diffraction order of the light diffracted by said diffraction grating structures, and θ the offset angle from the direction perpendicular to the grating line of one of said diffraction grating structures, the other diffraction grating structures being located outside the angular range of ±θ degrees which satisfies ##EQU11##
Claim 14
Dependent Claim 145 words
An observation apparatus comprising: a display element including a substrate and first and second display patterns formed on said substrate, each of said display patterns having diffraction grating structures; an illuminating system for supplying light to said display element; and an observation system disposed to allow for observation of the first and second display patterns produced by the light diffracted by said diffraction grating structure, wherein letting i denote the angle of incidence of light with respect to said substrate, λ the wavelength of incident light, P the grating period of said diffraction grating structures, K the diffraction order of the light diffracted by said diffraction grating structures, and θ the offset angle from the direction perpendicular to the grating line of one of said diffraction grating structures, the other diffraction grating structures being located outside the angular range of ±θ degrees which satisfies ##EQU11##
Claim 15
Dependent Claim 53 words
An observation apparatus according to claim 11, wherein said illuminating system is formed by an objective lens for forming an image of an object to be observed in the vicinity of said display element, and said first and second display patterns and the image of the object being observed by said observation system.

References Cited (Backward Citations)

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US4011435A Cited
US3997243A Cited
US4045124A Cited
US4251137A Cited
US4389096A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-08-14 1993-02-13 1993-08-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-08-14 1997-02-13 1997-08-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-08-14 2001-02-13 2001-08-15 $7700.00 Window Closed / Lapsed

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