Method and apparatus for measuring performance times of a shutter apparatus

Claim 2

Apparatus for electrically measuring performance times of a camera shutter apparatus of the type having a leading curtain and a trailing curtain which are caused to traverse a focal plane aperture at different times for the usual purpose of exposing film when the shutter apparatus is operated, comprising: first measuring means for measuring an elapsed time for a leading curtain to traverse a focal plane aperture; second measuring means for measuring an elapsed time for a trailing curtain to traverse the focal plane aperture; third measuring means for measuring a time period between the time that the leading curtain starts the traverse of the focal plane aperture and the time that the trailing curtain starts the traverse of the focal plane aperture; and display means operative in conjunction with the first, second and third measuring means for displaying at least one of the times measured.

Claim 3

An apparatus as recited in claim 1 further including selecting means for selecting among the various times measured to cause the selected time measurements to be displayed by the display means.

Claim 4

An apparatus as recited in claim 2 further including means for holding signals representative of the various times measured whereby the various times measured may be repeatedly selected for display after a single operation of the shutter apparatus.

Claim 5

An apparatus as recited in claim 1 further including means for determining the time difference between the time period measured by the third measuring means and the time period between the time that the leading curtain ends the traverse of the focal plane aperture and the time that the trailing curtain ends the traverse of the focal plane aperture.

Claim 6

An apparatus as recited in claim 1 wherein the camera is further of the type having a means for energizing a photoflash apparatus, and the invention further comprises: fourth measuring means for measuring a time delay between the time that the leading curtain starts the traverse of the focal plane aperture and the time of energization of a photoflash apparatus controlled by energizing means of the camera, and the display means is also operative in conjunction with the fourth measuring means.

Claim 7

An apparatus as recited in claim 5 further including selecting means for selecting among the various times measured to cause the selected time measurements to be displayed by the display means.

Claim 8

An apparatus as recited in claim 6 further including means for holding signals representative of the various times measured whereby the various times measured may be repeatedly selected for display after a single operation of the shutter apparatus.

Claim 9

An apparatus as recited in claim 5 wherein the invention further comprises: fifth measuring means for measuring a change in exposure time at the start and end of the traverse of the curtains across the focal plane aperture, by subtracting from the time period measured by the third measuring means the time period between the time that the leading curtain ends the traverse of the focal plane aperture and the time that the trailing curtain ends the traverse of the focal plane aperture, and the display means is also operative in conjunction with the fifth measuring means.

Claim 10

An apparatus as recited in claim 8 further including selecting means for selecting among the various times measured to cause the selected time measurements to be displayed by the display means.

Claim 11

An apparatus as recited in claim 9 further including means for holding signals representative of the various times measured whereby the various times measured may be repeatedly selected for display after a single operation of the shutter apparatus.

Claim 12

An apparatus as recited in claim 1 wherein the measuring means comprise: first and second photoelectric sensor means for providing an electrical signal during exposure to light, means for providing a light communication path to the first photoelectric sensor means from a position adjacent the edge of the focal plane aperture from which the curtains begin the traverse across the focal plane aperture, and means for providing a light communication path to the second photoelectric sensor means from a position adjacent the edge of the focal plane aperture from which the curtains end the traverse across the focal plane aperture.

Claim 13

An apparatus as recited in claim 11 wherein the measuring means further comprise: a clock means for providing clock pulses at a predetermined frequency, gating means for conducting clock pulses in accordance with the electrical signals provided from the first and second photoelectric sensor means, and counter means for counting the clock pulses conducted by the gating means and for providing outputs to the display means indicative of the counts.

Claim 14

An apparatus as recited in claim 5 wherein the measuring means comprise: first, second and third photoelectric sensor means for providing an electrical signal during exposure to light; means for providing a light communication path to the first photoelectric sensor means from a position adjacent the edge of the focal plane aperture from which the curtains begin the traverse across the focal plane aperture, means for providing a light communication path to the second photoelectric sensor means from a position adjacent the edge of the focal plane aperture from which the curtains end the traverse across the focal plane aperture, means for providing a light communication path to the third photoelectric sensor means for light provided from a photoflash apparatus controlled by the means of the camera for energizing a photoflash apparatus.

Claim 15

An apparatus as recited in claim 13 wherein the measuring means further comprise: a clock means for providing clock pulses at a predetermined frequency, gating means for conducting clock pulses in accordance with the electrical signals provided from the first, second and third photoelectric sensor means, and counter means for counting the clock pulses conducted by the gating means and for providing outputs to the display means indicative of the counts.

Claim 16

An apparatus as recited in claim 14 further comprising switching means for selectively switching the outputs of the counter means to the display means.

Claim 17

Apparatus for electrically measuring performance times of a shutter apparatus of a camera, comprising: first and second photoelectric sensor means for providing an electrical signal when exposed to light; means for providing a light communication path to the first photoelectric sensor means from a position relative to the shutter apparatus at which light will first pass through the shutter apparatus at the beginning of the exposure opening; means for providing a light communication path to the second photoelectric sensor means from a position relative to the shutter apparatus at which light will pass through the shutter apparatus at the beginning of the end of a full exposure opening; a clock means for providing clock pulses at a predetermined frequency; gating means, connected to the sensor means and the clock means, for conducting clock pulses in accordance with the electrical signals from the sensor means; counter means, connected to the gating means, for counting the clock pulses conducted by the gating means and for providing outputs indicative thereof; and display means, connected to the counter means, for displaying numbers indicative of the outputs supplied by the counter means.

Claim 18

Apparatus for electrically measuring performance times of a shutter apparatus of a camera, comprising: first and second photoelectric sensor means for providing an electrical signal when exposed to light; means for providing a light communication path to the first photoelectric sensor means from a position relative to the shutter apparatus at which light will first pass through the shutter apparatus at the beginning of the exposure opening; means for providing a light communication path to the second photoelectric sensor means from a position relative to the shutter apparatus at which light will pass through the shutter apparatus at the beginning of the end of a full exposure opening; a clock means for providing clock pulses at a predetermined frequency; gating means, connected to the sensor means and the clock means, for conducting clock pulses in accordance with the electrical signals from the sensor means; counter means, connected to the gating means, for counting the clock pulses conducted by the gating means and for providing outputs indicative thereof; and display means, connected to the counter means, for displaying numbers indicative of the outputs supplied by the counter means.

Claim 19

An apparatus as recited in claim 16 further including: switching means, connected with the counter means and display means, for selectively switching outputs of the counter means to the display means.

Claim 20

An apparatus as recited in claim 16 wherein the camera also includes means for energizing a photoflash apparatus, and the invention further includes: a third photoelectric sensor means, connected to the gating means, for providing an electrical signal when exposed to light; and means for providing a light communication path to the third photoelectric sensor means for light provided from a photoflash apparatus controlled by a means of the camera for energizing the photoflash apparatus.

Claim 21

An apparatus as recited in claim 18 further including: switching means, connected with the counter means and display means, for selectively switching outputs of the counter means to the display means.

Claim 22

A process for measuring the performance times of a shutter apparatus of a camera of the type having a leading curtain and a trailing curtain which are caused to traverse a focal plane aperture at different times for the usual purpose of exposing film when the shutter apparatus is operated, comprising: measuring an elapsed time for a leading curtain to traverse a focal plane aperture, measuring an elapsed time for a trailing curtain to traverse the focal plane aperture, measuring a first time period between the time that the leading curtain starts the traverse of the focal plane aperture and the time that the trailing curtain starts the traverse of the focal plane aperture, and displaying at least one of the times measured.

Claim 23

A process for measuring the performance times of a shutter apparatus of a camera of the type having a leading curtain and a trailing curtain which are caused to traverse a focal plane aperture at different times for the usual purpose of exposing film when the shutter apparatus is operated, comprising: measuring an elapsed time for a leading curtain to traverse a focal plane aperture, measuring an elapsed time for a trailing curtain to traverse the focal plane aperture, measuring a first time period between the time that the leading curtain starts the traverse of the focal plane aperture and the time that the trailing curtain starts the traverse of the focal plane aperture, and displaying at least one of the times measured.

Claim 24

A process as recited in claim 20 for use with a camera also having means for energizing a photoflash apparatus wherein the invention further comprises: measuring a time delay between the time that the leading curtain starts the traverse of the focal plane aperture and the time of energization of a photoflash apparatus controlled by the energizing means of the camera.

Claim 25

A process as recited in claim 21 further comprising: measuring a second time period between the time that the leading curtain ends the traverse of the focal plane aperture and the time that the trailing curtain ends the traverse of the focal plane aperture.

Claim 26

A process as recited in claim 22 further comprising: substracting the second time period measured from the first time period measured.

Claim 27

A process as recited in claim 20 further comprising: measuring a second time period between the time that the leading curtain ends the traverse of the focal plane aperture and the time that the trailing curtain ends the traverse of the focal plane aperture.

Claim 28

A process as recited in claim 24 further comprising: subtracting the second time period measured from the first time period measured.