Method of and apparatus for reading out image information

Claim 1

A method of reading out image information stored on a recording medium by detecting and photoelectrically converting emitted, transmitted or reflected light obtained from optical two-dimensional scanning of the image information on the recording medium, integrating the photoelectrically converted output signal according to a predetermined clock, and sampling the integration output, thereby reading out each picture element of the image information, which method comprises using a plurality of integrators, sequentially switching said integrators to start integration each time a first clock pulse determining the size of said picture element is input, setting the integration periods of said integrators to a value not shorter than one clock length of said first clock pulse so as to partially overlap each other, actuating the sampling of a signal from the started integrator by a second clock pulse at a point of time within the overlap region of the integration periods but outside the regions where the next integrator is in the switching transient state to integration start mode and where said started integrator is reset, and determining the reset state holding period of each integrator so that each integrator is sufficiently reset to prepare for the start of the next integration.

Claim 2

A method of reading out image information stored on a recording medium by detecting and photoelectrically converting emitted, transmitted or reflected light obtained from optical two-dimensional scanning of the image information on the recording medium, integrating the photoelectrically converted output signal according to a predetermined clock, and sampling the integration output, thereby reading out each picture element of the image information, which method comprises using a plurality of integrators, sequentially switching said integrators to start integration each time a first clock pulse determining the size of said picture element is input, setting the integration periods of said integrators to a value not shorter than one clock length of said first clock pulse so as to partially overlap each other, actuating the sampling of a signal from the started integrator by a second clock pulse at a point of time within the overlap region of the integration periods but outside the regions where the next integrator is in the switching transient state to integration start mode and where said started integrator is reset, and determining the reset state holding period of each integrator so that each integrator is sufficiently reset to prepare for the start of the next integration.

Claim 7

An apparatus for reading out image information stored on a recording medium by detecting and photoelectrically converting emitted, transmitted or reflected light obtained from optical two-dimensional scanning of the image information on the recording medium, integrating the photoelectrically converted output signal according to a predetermined clock, and sampling the integration output, thereby reading out each picture element of the image information, which apparatus comprises "n" integrators having reset switches and connected with a signal input terminal in parallel to one another, wherein n is an integer not smaller than 2, an integration start signal generating and supplying means for sequentially supplying the integration start signal to respective integrators at intervals of "n" clock period each after a delay of at least one clock length from the start of the preceding integrator at least based on the clock signal of a predetermined frequency, an integration mode holding time setting means capable of setting the integration mode holding time of each integrator to a value longer than one clock length, an integrator reset signal generating and supplying means for supplying a signal to reset each integrator at the end of said integration mode holding time and maintain it in the reset mode for a sufficient length of time, and a sampling pulse generating means which can set the sampling of the integration output of each integrator to a point of time after one clock length plus the reset switch off delay time of said integrator elapses from when the integration start signal is given to said integrator and which generates a sampling command at said point of time.

Claim 8

An apparatus for reading out image information stored on a recording medium by detecting and photoelectrically converting emitted, transmitted or reflected light obtained from optical two-dimensional scanning of the image information on the recording medium, integrating the photoelectrically converted output signal according to a predetermined clock, and sampling the integration output, thereby reading out each picture element of the image information, which apparatus comprises "n" integrators having reset switches and connected with a signal input terminal in parallel to one another, wherein n is an integer not smaller than 2, an integration start signal generating and supplying means for sequentially supplying the integration start signal to respective integrators at intervals of "n" clock period each after a delay of at least one clock length from the start of the preceding integrator at least based on the clock signal of a predetermined frequency, an integration mode holding time setting means capable of setting the integration mode holding time of each integrator to a value longer than one clock length, an integrator reset signal generating and supplying means for supplying a signal to reset each integrator at the end of said integration mode holding time and maintain it in the reset mode for a sufficient length of time, and a sampling pulse generating means which can set the sampling of the integration output of each integrator to a point of time after one clock length plus the reset switch off delay time of said integrator elapses from when the integration start signal is given to said integrator and which generates a sampling command at said point of time.