Electronic flash apparatus controlled by a digital memory system

Claim 2

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said oscillator means including a photosensitive means for responding to light, including flash illumination provided by said flash means, for providing in response to the intensity of the light received by said photosensitive means pulses the frequency of which is directly proportional to said intensity.

Claim 3

The combination of claim 1 and wherein said terminating means is connected to said counting means for terminating the operation thereof when a given number of pulses have been counted thereby, whereby the time required for counting said number of pulses is shorter at higher light intensities as compared to lower light intensity, said flash control means being operatively connected with said terminating means for responding to termination of the operation of said counting means by said terminating means when said given number of pulses have been counted for controlling said flash means to discontinue flash illumination when said given number of pulses have been counted by said counting means.

Claim 4

The combination of claim 1 and wherein an adjusting means forms part of a camera for adjusting one of said parameters, and means operatively connected with said terminating means and with said adjusting means for automatically setting said terminating means to bring about termination of the operation of said counting means according to the selected adjustment of said parameter by said adjusting means.

Claim 5

The combination of claim 3 and wherein said adjusting means adjusts the diaphragm aperture of the camera.

Claim 6

The combination of claim 1 and wherein said oscillator means is in the form of a sine wave oscillator.

Claim 7

The combination of claim 1 and wherein an adjusting means is operatively connected with said oscillator means for adjusting the latter according to one of said parameters.

Claim 8

The combination of claim 1 and wherein a frequency divider means is situated between and operatively connected with said oscillator means and counting means and said frequency divider means influencing the transmission of information from said oscillator means to said counting means according to one of said parameters.

Claim 9

In an electronic flash aparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, an indicating means being operatively connected with said counting means for indicating to the operator whether or not said flash means has provided flash illumination sufficient for said counting means to operate until said terminating means terminates the operation thereof.

Claim 10

In an electronic flash aparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, an indicating means being operatively connected with said counting means for indicating to the operator whether or not said flash means has provided flash illumination sufficient for said counting means to operate until said terminating means terminates the operation thereof.

Claim 11

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said oscillating means including a selecting means available to the operator for manually selecting the frequency of pulses provided by said oscillating means according to the distance of the object from said flash means with the selected frequency being inversely proportional to said distance.

Claim 12

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said oscillating means including a selecting means available to the operator for manually selecting the frequency of pulses provided by said oscillating means according to the distance of the object from said flash means with the selected frequency being inversely proportional to said distance.

Claim 13

The combination of claim 9 and wherein said oscillating means includes a plurality of separate oscillating units which respectively provide pulses at different frequencies so that one of said units is available for selection by the operator according to the distance of the object from said flash means.

Claim 14

The combination of claim 9 and wherein said oscillating means includes a single oscillating unit and said selecting means includes an adjusting means connected with said single unit for adjusting the latter to provide a selected frequency according to the distance of the object from said flash means.

Claim 15

The combination of claim 9 and wherein an indicating means is operatively connected with said counting means for indicating to the operator whether or not the pulse frequency has been accurately selected according to the distance of the object from said flash means.

Claim 16

The combination of claim 12 and wherein said flash means is operable for providing first a preliminary flash and then a main flash to be utilized during film exposure, and photosensitive means for responding to said preliminary flash and operatively connected with said counting means and through the latter with said indicating means for actuating the latter to indicate to the operator the pulse frequency to be selected according to the distance of the object from said flash means.

Claim 17

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulse, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said oscillating means providing pulses at a number of different constant frequencies one of which is to be selected according to the distance of the object from said flash means, and photosensitive means responding to operation of said flash means and operatively connected with said oscillating means for automatically selecting a frequency for the pulses produced by said oscillating means which is proper according to the distance of the object from said flash means.

Claim 18

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulse, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said oscillating means providing pulses at a number of different constant frequencies one of which is to be selected according to the distance of the object from said flash means, and photosensitive means responding to operation of said flash means and operatively connected with said oscillating means for automatically selecting a frequency for the pulses produced by said oscillating means which is proper according to the distance of the object from said flash means.

Claim 19

The combination of claim 14 and wherein an indicating means is operatively connected with said counting means for indicating to the operator when the conditions are such that a proper exposure cannot be made, so that the operator then can change the conditions to achieve a proper exposure.

Claim 20

The combination of claim 14 and wherein said means for automatically selecting said pulse frequency of said oscillating means includes a photosensitive converting circuit means responding to flash illumination for converting the latter into a given signal, and selecting circuit means connected between said converting circuit means and said oscillating means for responding to said signal of said converting circuit means for automatically selecting at said oscillating means a pulse frequency according to said signal and thus according to the distance of the object from said flash means.

Claim 21

The combination of claim 14 and wherein said means for automatically selecting pulse frequency responds automatically to light, including flash illumination, reflected from the object for progressively changing the selected pulse frequency from a lesser pulse frequency to progressively higher pulse frequencies according to the light intensity.

Claim 22

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said flash means providing first a preliminary flash illumination and thereafter a main flash illumination to be utilized during actual film exposure, said counting means counting the pulses provided by said oscillating means during preliminary flash illumination, and said counting means memorizing the number of pulses counted by said counting means upon termination of the operation thereof by said terminating means, said flash control means being operatively connected with said counting means to be controlled thereby and including a reference pulse means for providing reference pulses of a given constant frequency during film exposure while said flash means provides said main flash illumination, and said flash control means including a comparing means for comparing the reference pulses produced by said reference pulse means and the number of pulses counted by said counting means for actuating said flash means to terminate main flash illumination when the reference pulses have a given relationship with respect to the pulses counted by said counting means according to the preliminary flash illumination.

Claim 23

In an electronic flash apparatus, flash means for providing flash illumination, oscillator means for providing pulses during operation of said flash means, counting means operatively connected with said oscillator means for counting said pulses, terminating means operatively connected with said counting means for selectively terminating operation thereof according to one or more parameters such as film speed, diaphragm aperture, and the like, and flash control means operatively connected with said flash means for controlling the extent of flash illumination provided thereby, said counting means and said terminating means forming a pair of means one of which is operatively connected with said flash control means for operating the latter, said flash means providing first a preliminary flash illumination and thereafter a main flash illumination to be utilized during actual film exposure, said counting means counting the pulses provided by said oscillating means during preliminary flash illumination, and said counting means memorizing the number of pulses counted by said counting means upon termination of the operation thereof by said terminating means, said flash control means being operatively connected with said counting means to be controlled thereby and including a reference pulse means for providing reference pulses of a given constant frequency during film exposure while said flash means provides said main flash illumination, and said flash control means including a comparing means for comparing the reference pulses produced by said reference pulse means and the number of pulses counted by said counting means for actuating said flash means to terminate main flash illumination when the reference pulses have a given relationship with respect to the pulses counted by said counting means according to the preliminary flash illumination.

Claim 24

The combination of claim 18 and wherein said oscillating means provides different constant frequencies according to the distance of the object from said flash means, and photosensitive selecting means responding also to preliminary flash illumination for automatically selecting at least one of said constant frequencies.

Claim 25

The combination of claim 18 and wherein said oscillating means includes a photosensitive means responding to preliminary flash illumination for operating said oscillating means to provide automatically a pulse frequency which is directly proportional to light intensity received by said photosensitive means.