Analog signal switching device for use in an optical memory

A signal switching device for use in an optical memory device having a recording/erasing mode and a mode other than said recording/erasing mode comprising:

• means for producing a switch control signal which is in a first state during said recording/erasing mode and in a second state during said mode other than said recording/erasing mode;
• an analog switch for receiving first and second input signals and for producing as an output said first input signal during the second state of said switch control signal, and said second input signal during the first state of said switch control signal by a switching operation;
• a mask signal generator for generating a mask signal which covers a period during the first state of said switch control signal so as to cover a period during the switching operation of said analog switch;
• and
• a gate means controlled by said mask signal for allowing said first input signal to pass therethrough during the absence of said mask signal and for preventing said second input signal to pass therethrough during the presence of said mask signal, whereby noise signals produced by the switching operation of said analog switch are eliminated.

An analog signal switching device for use in an optical memory device having a recording/erasing mode and a mode other than said recording/erasing mode comprising:

• means for producing a switch control signal which is in a first state during said recording/erasing mode and in a second state during said mode other than said recording/erasing mode;
• sample hold circuit means for holding an input analog signal during the second state of said switch control signal;
• an analog switch for receiving said input analog signal and said held input analog signal from said sample hold circuit means and for producing as an output said input analog signal during the second stage of said switch control signal, and said held input analog signal during the first state of said switch control signal by a switching operation;
• a mask signal generator for generating a mask signal which covers a period during the first state of said switch control signal so as to cover a period during the switching operation of said analog switch;
• a digital signal generator for generating a digital signal converted from said analog signal produced from said analog switch;
• and
• a gate means controlled by said mask signal for allowing a digital signal corresponding to said input analog signal to pass therethrough during the absence of said mask signal and for preventing a digital signal corresponding to said held input analog signal to pass therethrough during the presence of said mask signal, whereby noise signals produced by the switching operation of said analog switch are eliminated.