| 摘要 |
PURPOSE:To set fixed inspecting conditions and also to shorten checking/ recording time by automating the production of a focus offset signal, the detection of a track error signal and the recording of data respectively. CONSTITUTION:An integrator 5 integrates an original point, pulse (a) and the envelope signal (h) of each cycle and delivers an integration signal (i). This signal (i) is equal to the sum total of track error signals (g) equivalent to one round of an optical disk. An optically focust point is coincident with the position where the sum total of the signals (g) is maximum. An A/D converter 6 peak- holds the signal (i) and converts it into the digital data with a sample pulse (b), i.e., the output of a timing pulse generator 1. A memory part 7 contains an address counter and the count value of this counter and the contents of all addresses are cleared to zero by initialization. The output of the converter 6 is written to an address designated by the address counter at the rise of a writing pulse (c), i.e., the other output of the generator 1. The count value of the address counter is updated at the fall of the pulse (c) and an address is designated for writing the next data. |
