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EP0307203A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Tri-color separating optical system

Assignee: Victor Company of Japan Ltd
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Filing: 1988-09-08
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Granted: —
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Expires: 2008-09-08
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Abstract

Abstract To form three different color optical images in close vicinity to each other on the same image forming plane in a tri-color separating optical system, the optical system comprising a lens for focusing a subject optical image on a green optical image forming plane (I g ); dichroic mirrors (D b and D r ) or a dichroic prism for directly passing a green color image and reflecting a blue color image in the first direction and a red color image in the second direction; a first prism (P b ) having therein a total reflection surface (M b ) and an extended optical path length for reflecting the blue color image to a blue optical image-forming plane (I b ); and a second prism (P r ) having therein a total reflection surface (M r ) and an extended optical path length for reflecting the red color image to a red optical image-forming plane (I r ).

Inventors

  • 👤 Hirohiko C-428 Okurayama A2-Coporasu Shinonaga
  • 👤 Itsuo Takanashi
  • 👤 Shintaro Nakagaki
  • 👤 Tsutou 301 Lilac House 2-177 Asakura
  • 👤 Masato C1-3 Nippon Victor Nobi Ryo Furuya

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-02 00:26
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/1006; G02B27/1013; G02B27/14; G02B27/145; G02B27/149; H; H04; H04N; H04N23/00; H04N23/10; H04N23/13; H04N23/16

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 239 words
A tri-color separating optical system for separating an optical image of a subject into three different color optical images, which comprises: (a) focusing means for focusing the subject optical image on a first optical image forming plane (I g ); (b) dichroic reflecting means, optically coupled to said focusing means, for directly passing a first color optical image therethrough and reflecting a second color optical image in a first direction therefrom, and a third color optical image in a second direction opposite to the first direction therefrom; (c) first optical block means having therein a first total reflection surface optically coupled to said dichroic reflecting means and a first extended optical path length, for reflecting the second color optical image reflected from said dichroic reflecting means in the first direction to a second optical image forming plane (I b ) through the first extended optical path length; and (d) second optical block means having therein a second total reflection surface optically coupled to said dichroic reflecting means and a second extended optical path length, for reflecting the third color optical image reflected from said dichroic reflecting means in the second direction to a third optical image forming plane (I r ) through the second extended optical path length; the first, second and third different-color optical image forming planes (I g , I b , I r ) being aligned with each other in close vicinity on a single plane.
Claim 2
Dependent Claim 239 words
A tri-color separating optical system for separating an optical image of a subject into three different color optical images, which comprises: (a) focusing means for focusing the subject optical image on a first optical image forming plane (I g ); (b) dichroic reflecting means, optically coupled to said focusing means, for directly passing a first color optical image therethrough and reflecting a second color optical image in a first direction therefrom, and a third color optical image in a second direction opposite to the first direction therefrom; (c) first optical block means having therein a first total reflection surface optically coupled to said dichroic reflecting means and a first extended optical path length, for reflecting the second color optical image reflected from said dichroic reflecting means in the first direction to a second optical image forming plane (I b ) through the first extended optical path length; and (d) second optical block means having therein a second total reflection surface optically coupled to said dichroic reflecting means and a second extended optical path length, for reflecting the third color optical image reflected from said dichroic reflecting means in the second direction to a third optical image forming plane (I r ) through the second extended optical path length; the first, second and third different-color optical image forming planes (I g , I b , I r ) being aligned with each other in close vicinity on a single plane.
Claim 3
Dependent Claim 67 words
The tri-color separating optical system of claim 1, wherein the first or second extended optical path length is determined in accordance with a formula as x = d(n - 1)n where x denotes an extended amount of optical path length; d denotes an optical path length of said first or second optical block means; and n denotes a refraction index of material of said optical block means.
Claim 4
Dependent Claim 18 words
The tri-color separating optical system of claim 1, wherein said focusing means is an image pickup convex lens.
Claim 5
Dependent Claim 62 words
The tri-color separating optical system of claim 1, wherein said dichroic reflecting means is a dichroic mirror composed of a first mirror for reflecting only the blue color optical image and passing through the red and green color optical images and a second mirror for reflecting only the red color optical image and passing through the blue and green color optical images.
Claim 6
Dependent Claim 64 words
The tri-color separating optical system of claim 1, wherein said dichroic reflecting means is a dichroic prism having a first dichroic mirror surface for reflecting only the blue color optical image and passing through the red and green color optical images and a second dichroic mirror surface for reflecting only the red color optical image and passing through blue and green color optical images.
Claim 7
Dependent Claim 35 words
The tri-color separating optical system of claim 1, wherein said first and second optical block means are first and second prisms each formed with a total reflection surface and an extended optical path length, respectively.
Claim 8
Dependent Claim 50 words
A color image pickup apparatus, comprising: (a) a tri-color separating optical system for separating an optical image of a subject into three different color optical images, as recited in claim 1; and (b) photoelectric transducing elements arranged on the first, second and third different color optical image forming planes, respectively.

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