In an optical signal readout apparatus including a source of laser light, {TAIL ~ a rotary disc record}, a photo detector, and an optical scanner for focusing light from the source onto the record and directing {HEAD ~ light} reflected back from the record onto the photo detector, the improvements characterized by: 
In an optical signal readout apparatus including a source of laser light , { TAIL ~ a rotary disc record } , a photo detector , and an optical scanner for focusing light from the source onto the record and directing { HEAD ~ light } reflected back from the record onto the photo detector , the improvements characterized by :
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