US4742397A — System and method for adjusting image brightness …

Claim 1

Independent Claim 239 words

An electronic printer for displaying an image for photographic reproduction comprising: display means for visually displaying the image to be photographed; photoresponsive means for detecting the intensity of light emanating from said display means and providing an output signal corresponding to the intensity of light so detected; comparator means for comparing the output signal from said photoresponsive means with a select one of a plurality of different voltage reference signals and providing an output signal indicative of said comparison; and control means for initially applying a steady state select voltage to said display means in place of an image defining electronic information signal so that said display means displays a substantially uniform light intensity; for thereafter adjusting, if necessary, the light intensity of said display means in response to the output of said comparator means so that the light intensity of said display means corresponds to said one select voltage reference signal; for thereafter applying an image defining electronic information signal in place of said steady state select voltage to said display means so that said display means displays the image to be photographed; for thereafter selecting, if necessary, other ones of said plurality of different voltage reference signals until the output signal from said comparator means meets a select condition; and for thereafter adjusting, if necessary, the light intensity of said display means as a function of the different voltage reference signals selected in the immediately preceding step.

Claim 2

Dependent Claim 239 words

An electronic printer for displaying an image for photographic reproduction comprising: display means for visually displaying the image to be photographed; photoresponsive means for detecting the intensity of light emanating from said display means and providing an output signal corresponding to the intensity of light so detected; comparator means for comparing the output signal from said photoresponsive means with a select one of a plurality of different voltage reference signals and providing an output signal indicative of said comparison; and control means for initially applying a steady state select voltage to said display means in place of an image defining electronic information signal so that said display means displays a substantially uniform light intensity; for thereafter adjusting, if necessary, the light intensity of said display means in response to the output of said comparator means so that the light intensity of said display means corresponds to said one select voltage reference signal; for thereafter applying an image defining electronic information signal in place of said steady state select voltage to said display means so that said display means displays the image to be photographed; for thereafter selecting, if necessary, other ones of said plurality of different voltage reference signals until the output signal from said comparator means meets a select condition; and for thereafter adjusting, if necessary, the light intensity of said display means as a function of the different voltage reference signals selected in the immediately preceding step.

Claim 3

Dependent Claim 69 words

The electronic printer of claim 1 wherein said display means comprises a cathode ray tube having cathode and grid terminals and said control means applies said steady state voltage and said image defining electronic information signal to the cathode terminal of said cathode ray tube and adjusts the light intensity of said cathode ray tube by varying the voltage applied to the grid terminal of said cathode ray tube.

Claim 4

Dependent Claim 53 words

The electronic printer of claim 2 wherein said control means comprises a first plurality of resistors and first switch means for connecting said resistors in select parallel relationship with respect to each other, said switch means being selectively controlled to vary the voltage applied to the grid terminal of said cathode ray tube.

Claim 5

Dependent Claim 51 words

The electronic printer of claim 3 wherein said control means comprises a second plurality of resistors and a second switch means for connecting said resistors in select parallel relationship with respect to each other, said switch means being selectively controlled to select one of said plurality of different voltage reference signals.

Claim 6

Dependent Claim 37 words

The electronic printer of claim 2 wherein said cathode ray tube displays a plurality of succeeding television fields and said control means responds to the output of said comparator means only about the middle of each field.

Claim 7

Dependent Claim 40 words

The electronic printer of claim 5 wherein said select condition of the output signal from said comparator means corresponds to the output signal from said photoresponsive means not exceeding the select one of said plurality of different voltage reference signals.

Claim 8

Dependent Claim 13 words

The electronic printer of claim 6 wherein said control means includes a microprocessor.

Claim 9

Independent Claim 205 words

A method for adjusting the image brightness in a system for displaying images for photographic reproduction comprising the steps of: applying a steady state select voltage to an image display device so that said display device displays a generally uniform light intensity; detecting the intensity of light emanating from said display device and providing a first output signal corresponding to the intensity of light so detected; comparing said first output signal with a select one of a plurality of different voltage reference signals and providing a second output signal indicative of said comparison; adjusting, if necessary, the light intensity of said display means in response to said second output signal so that the light intensity of said display means corresponds to said one select voltage reference signal; applying an image defining electronic information signal in place of said steady state select voltage to said display means so that said display means displays the image to be photographed; selecting, if necessary, other ones of said plurality of different voltage reference signals until said second output signal meets a select condition; and adjusting, if necessary, the light intensity of said display means as a function of the different voltage reference signals selected in the immediately preceding step.

Claim 10

Independent Claim 205 words

A method for adjusting the image brightness in a system for displaying images for photographic reproduction comprising the steps of: applying a steady state select voltage to an image display device so that said display device displays a generally uniform light intensity; detecting the intensity of light emanating from said display device and providing a first output signal corresponding to the intensity of light so detected; comparing said first output signal with a select one of a plurality of different voltage reference signals and providing a second output signal indicative of said comparison; adjusting, if necessary, the light intensity of said display means in response to said second output signal so that the light intensity of said display means corresponds to said one select voltage reference signal; applying an image defining electronic information signal in place of said steady state select voltage to said display means so that said display means displays the image to be photographed; selecting, if necessary, other ones of said plurality of different voltage reference signals until said second output signal meets a select condition; and adjusting, if necessary, the light intensity of said display means as a function of the different voltage reference signals selected in the immediately preceding step.

Claim 11

Dependent Claim 69 words

The method of claim 8 wherein: the display device comprises a cathode ray tube having cathode and grid terminals, said steady state voltage and said image defining electronic information signal are applied to the cathode terminal of the cathode ray tube and said adjustment to the light intensity of the cathode ray tube is accomplished by varying the voltage applied to the grid terminal of the cathode ray tube.

Claim 12

Dependent Claim 38 words

The method of claim 9 wherein the grid voltage applied to the grid terminal of the cathode ray tube is varied by switching select ones of a plurality of resistors into parallel relation with respect to each other.

Claim 13

Dependent Claim 36 words

The method of claim 10 wherein said select one of said plurality of different voltage reference signals is selected by switching select ones of a plurality of resistors into parallel relation with respect to each other.

Claim 14

Dependent Claim 45 words

The method of claim 9 wherein said cathode ray tube displays a plurality of succeeding television fields and said steps conducted in response to said second output signal are timed to respond to said second output signal only about the middle of each said field.

Claim 15

Dependent Claim 36 words

The method of claim 12 wherein said select condition of said second output signal corresponds to the output signal from said photoresponsive means not exceeding the select one of said plurality of different voltage reference signals.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1991-05-03	1991-11-02	1992-05-03	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1995-05-03	1995-11-02	1996-05-03	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1999-05-03	1999-11-02	2000-05-03	$7700.00	Window Closed / Lapsed

System and method for adjusting image brightness in electronic printer

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