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US4518258A Expired / Lapsed US ⏱️ 0.0 years remaining

Colour analyser

Assignee: Individual
•
Filing: 1980-10-15
•
Granted: 1985-05-21
•
Expires: 2000-10-15
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Abstract

Abstract A color analyser measuring the light intensities of at least three different colors within the spectrum of the incident light, and relating these measurements to values programmmed before. Those color components of the incident light that have to be influenced in order to conform to the preprogrammed relations are indicated by means of a color star, consisting of three rows of light sources (23, 24, 25) of appropriate colors. While influencing the color of the light with correction filters the operator views the change simultaneously at the color star. It is indicated in such a way that the light sources of the color star are extinguished as soon as the preprogrammed relations between the colors are satisfied, notwithstanding the absolute value of light intensity. An automatic exposure time meter is built in, also controlling an electronic timer (32).

Inventors

  • 👤 Harmen Broersma

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 15:19
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/46; G01J3/50; G01J3/51; G01R; G01R13/00; G01R13/40; G01R13/404; G01R13/405; G03; G03B; G03B27/00; G03B27/72; G03B27/73; G03B27/735

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 163 words
A colour analyser for measuring the relative intensities of a plurality of frequency components of light, comprising: sensor means for simultaneously developing a plurality of signals respectively proportional to the intensities of a plurality of frequency components of light; means operative on said proportional signals for determining which one represents the frequency component having the least intensity and for subtracting that one signal from at least each of the other ones of said proportional signals; display means for simultaneously displaying the results of said subtractions; additional circuitry that converts one or more signals of the analyser automatically into an indication of an exposure time needed to properly expose photosensitive materials; and regulator means for permitting an operator to program said conversion for photosensitive materials having different reciprocity characteristics, said regulating means including means for setting the quotient of the logarithm of a measured light intensity divided by the logarithm of said exposure time to at least two different values, namely 1.0 and 1.2.
Claim 2
Dependent Claim 163 words
A colour analyser for measuring the relative intensities of a plurality of frequency components of light, comprising: sensor means for simultaneously developing a plurality of signals respectively proportional to the intensities of a plurality of frequency components of light; means operative on said proportional signals for determining which one represents the frequency component having the least intensity and for subtracting that one signal from at least each of the other ones of said proportional signals; display means for simultaneously displaying the results of said subtractions; additional circuitry that converts one or more signals of the analyser automatically into an indication of an exposure time needed to properly expose photosensitive materials; and regulator means for permitting an operator to program said conversion for photosensitive materials having different reciprocity characteristics, said regulating means including means for setting the quotient of the logarithm of a measured light intensity divided by the logarithm of said exposure time to at least two different values, namely 1.0 and 1.2.

References Cited (Backward Citations)

US3097563A Cited
US2203036A Cited
US3408142A Cited
CH531760A Cited
US3819275A Cited
NL7306374A Cited
DE2409909A1 Cited
US4125330A Cited
US4025190A Cited
US4194838A Cited
FR2390333A1 Cited
US4140391A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-05-20 1988-11-19 1989-05-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-05-20 1992-11-19 1993-05-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-05-20 1996-11-19 1997-05-21 $7700.00 Window Closed / Lapsed

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