US4375918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color correction apparatus for a duplicate camera
Assignee: Dainippon Screen Manufacturing Co Ltd
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Filing: 1981-08-31
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Granted: 1983-03-08
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Expires: 2001-08-31
Abstract
Abstract A color correction apparatus for a duplicate camera wherein three color correction filters of three primary colors are provided and are selectively interposed into the exposure light path, is disclosed. An arithmetic unit is connected to a color correction value setup means which sets up color correction values of colors to be removed from an original picture, and it receives these density values as negative values and subtracts the minimum value thereof from each of the other density values to outputs a color correction signal. Then, a control unit connected to the arithmetic unit controls the color correction filters so that they may be interposed into the exposure light path according to the color correction signal.
Inventors
- 👤 Koichi Isono
- 👤 Tsuneo Takagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:23
CPC Classifications
G; G03; G03B; G03B27/00; G03B27/72; G03B27/73; G03B27/735; G03F; G03F3/00; G03F3/10; G03F3/101
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
153 words
A color correction apparatus for a duplicate camera wherein three color correction filters of three primary colors are provided and are selectively interposed into the exposure light path, comprising: (a) color correction value setup means which sets up color correction values of colors to be removed from the tone of an original picture; (b) an arithmetic unit which is connected to the color correction value setup means and which inputs the density values set up in the color correction value setup means as negative values and subtracts the minimum value of the density values input from each of the other density values to output a color correction signal corresponding to the differences subtracted of the density values; and (c) a control unit which is connected to the arithmetic unit and which controls the color correction filters so that they may be interposed into the exposure light path according to the color correction signal.
Claim 2
Dependent Claim
153 words
A color correction apparatus for a duplicate camera wherein three color correction filters of three primary colors are provided and are selectively interposed into the exposure light path, comprising: (a) color correction value setup means which sets up color correction values of colors to be removed from the tone of an original picture; (b) an arithmetic unit which is connected to the color correction value setup means and which inputs the density values set up in the color correction value setup means as negative values and subtracts the minimum value of the density values input from each of the other density values to output a color correction signal corresponding to the differences subtracted of the density values; and (c) a control unit which is connected to the arithmetic unit and which controls the color correction filters so that they may be interposed into the exposure light path according to the color correction signal.
Claim 3
Dependent Claim
143 words
An apparatus as defined in claim 1, wherein the color correction value setup means comprising optional color correction value setup means which sets up color correction density values depending on optional factors such as a color tendency of the original picture, and basic color correction value setup means which sets up color correction density values depending on mechanical factors such as a nature and characteristics of the photosensitive material, and wherein the arithmetic unit subtracts each color correction density value of each color which is set up in the optional color correction setup means from the corresponding color correction density value of each color which is set up in the basic color correction setup means and then further subtracts the minimum value of the obtained density values in the subtraction from each of the other density values to output a color correction signal.
Claim 4
Dependent Claim
22 words
An apparatus as defined in claim 1 or 2, wherein the color correction value setup means comprising setup units of primary colors.
Claim 5
Dependent Claim
19 words
An apparatus as defined in claim 3, wherein a base 10 digital switch is used for the setup unit.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-07 | 1986-09-06 | 1987-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-07 | 1990-09-06 | 1991-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-07 | 1994-09-06 | 1995-03-08 | $7700.00 | Window Closed / Lapsed |