EP0167289A2
Expired / Lapsed
EP
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Transparency apparatus
Assignee: Wacom Co Ltd
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Filing: 1985-06-03
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Granted: —
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Expires: 2005-06-03
Abstract
Abstract A transparency apparatus has a generally rectangular tabular light guide plate (1) having a flat upper surface (11), the underside of the light guide plate having at least one tapered surface (15,16) which extends from near a light- receiving end surface (13,14) of the light guide plate such as to progressively approach the flat upper surface of the light guide plate. The tapered surface is provided with fine convexities and concavities. The portion (17) of the upper surface opposing the tapered surface presents an area on which an observation plate is to be seated and the transparency can be placed on the observation plate.
Inventors
- 👤 Yoji Eto
- 👤 Hideo Sawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 02:27
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0033; G02B6/0035; G02B6/0045; G02B6/0046; G02B6/005; G02B6/0066; G02B6/0068; G02B6/007; G02B6/0071; G02B6/0081
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
135 words
Apparatus for observation of a transparency such as a photographic film placed on a translucent observation plate, comprising: a generally rectangular tabular light guide plate (1) having a flat upper surface (11), the underside of said light guide plate having at least one tapered surface (15,16) which extends from a portion of said light guide plate near a longitudinal end surface (13,14) of said light guide plate towards the other end such as to progressively approach said flat upper surface (11) of said light guide plate, the portion of said upper surface opposing said tapered surface presenting an area on which said observation plate is to be seated; and a light source means (3,4) from which a light is introduced into said light guide plate through said end surface (13,14) of said light guide plate.
Claim 2
Dependent Claim
135 words
Apparatus for observation of a transparency such as a photographic film placed on a translucent observation plate, comprising: a generally rectangular tabular light guide plate (1) having a flat upper surface (11), the underside of said light guide plate having at least one tapered surface (15,16) which extends from a portion of said light guide plate near a longitudinal end surface (13,14) of said light guide plate towards the other end such as to progressively approach said flat upper surface (11) of said light guide plate, the portion of said upper surface opposing said tapered surface presenting an area on which said observation plate is to be seated; and a light source means (3,4) from which a light is introduced into said light guide plate through said end surface (13,14) of said light guide plate.
Claim 3
Dependent Claim
41 words
Apparatus according to claim 1, further comprising fine convexities and concavities formed on said tapered surface (15,16) of said light guide plate (1), and a reflecting mirror (2) disposed such as to oppose said tapered surface of said light guide plate.
Claim 4
Dependent Claim
31 words
Apparatus according to claim 1 or claim 2, wherein said light source means has a light source (3,4) disposed in the vicinity of said end surface of said light guide plate.
Claim 5
Dependent Claim
23 words
Apparatus according to claim 3 wherein the light source is generally aligned with and in the plane of the light guide plate (1).
Claim 6
Dependent Claim
21 words
Apparatus according to any one of the preceding claims wherein the light guide plate (1) is made of acrylic plastics material.
References Cited (Backward Citations)
No citation records indexed.
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