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US4473294A Expired / Lapsed US ⏱️ 0.0 years remaining

Copying apparatus

Assignee: Toshiba Corp
•
Filing: 1982-07-26
•
Granted: 1984-09-25
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Expires: 2002-07-26
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Abstract

Abstract A copying apparatus comprises original sheet holder provided with a plane on which an original sheet is to be mounted, exposure system provided with a lens to guide light rays reflected from an impression indicated on the original sheet mounted on the holder to cause the original sheet impression to be focused on a photosensitive layer. A detector for detecting data on an average original density of the original sheet impression denoted by the light rays is set between the photosensitive layer and lens to receive part of the light rays reflected from the original sheet, on a line extending from the center of the lens to the center of that portion of the photosensitive layer which corresponds to the smallest original sheet among those which are to be mounted on the original sheet holder.

Inventors

  • 👤 Akiro Iimori

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 20:42
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/50; G03G15/5025

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 257 words
A copying apparatus which comprises: original sheet holding means provided with a plane on which an original sheet is to be mounted; exposure means provided with a lens to guide light rays reflected from an impression indicated on the original sheet mounted on said holding means to cause the original sheet impression to be focused on a prescribed image forming plane, said light rays denoting data on an original density of the original sheet impression; a photosensitive layer formed in conformity with the prescribed image forming plane; and detecting means for detecting data on the original desity of the original sheet impression denoted by the light rays, which is set between the prescribed image forming plane and lens to receive part of the light rays reflected from the original sheet, on a line extending from the center of the lens to the center of that portion of the image forming plane which corresponds to the smallest original sheet among those which are to be mounted on the original sheet holding means, and wherein said intensity detecting means includes a light intensity detector which is set at a distance L from the lens to receive part of light rays reflected from the impression indicated on the original sheet, said distance being so defined as to satisfy the following equation: ##EQU2## where, φ: diameter of the lens l: a distance between the lens and the photosensitive layer S: the width of that portion of the photosensitive layer which corresponds to that of the impression on the smallest original sheet.
Claim 2
Dependent Claim 257 words
A copying apparatus which comprises: original sheet holding means provided with a plane on which an original sheet is to be mounted; exposure means provided with a lens to guide light rays reflected from an impression indicated on the original sheet mounted on said holding means to cause the original sheet impression to be focused on a prescribed image forming plane, said light rays denoting data on an original density of the original sheet impression; a photosensitive layer formed in conformity with the prescribed image forming plane; and detecting means for detecting data on the original desity of the original sheet impression denoted by the light rays, which is set between the prescribed image forming plane and lens to receive part of the light rays reflected from the original sheet, on a line extending from the center of the lens to the center of that portion of the image forming plane which corresponds to the smallest original sheet among those which are to be mounted on the original sheet holding means, and wherein said intensity detecting means includes a light intensity detector which is set at a distance L from the lens to receive part of light rays reflected from the impression indicated on the original sheet, said distance being so defined as to satisfy the following equation: ##EQU2## where, φ: diameter of the lens l: a distance between the lens and the photosensitive layer S: the width of that portion of the photosensitive layer which corresponds to that of the impression on the smallest original sheet.
Claim 3
Dependent Claim 37 words
The copying apparatus according to claim 1, wherein the original sheet holding means is provided with a base line along which one side of each of the respective original sheets having different sizes is to be set
Claim 4
Dependent Claim 19 words
The copying apparatus according to claim 2, wherein said base line includes one edge of the original sheet-mounting plane.
Claim 5
Dependent Claim 67 words
The copying apparatus according to claim 1, wherein the light intensity detector is provided with a light-receiving section having a maximum sensitivity to light rays at the center thereof, said section having the maximum sensitivity to light rays being positioned on the line extending from the center of the lens to the center of that part of the photosensitive layer which corresponds to the smallest original sheet.
Claim 6
Dependent Claim 47 words
The copying apparatus according to claim 1, wherein the exposure means provided with a lamp for illuminating the impression indicated on the original sheet mounted on the holding means, and said detecting means is connected to the lamp to control an intensity light rays from the lamp.

References Cited (Backward Citations)

US3926518A Cited
US3947117A Cited
US4017180A Cited
GB1564046A Cited
US4193674A Cited
US4334767A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-09-25 1988-03-26 1988-09-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-09-25 1992-03-26 1992-09-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-09-25 1996-03-26 1996-09-25 $7700.00 Window Closed / Lapsed

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