JPH0349628U

JPH0349628U -

Info

Publication number: JPH0349628U
Application number: JP10947289U
Authority: JP
Priority date: 1989-09-19
Filing date: 1989-09-19
Publication date: 1991-05-15

Description

[Brief explanation of drawings]

第１図は本考案に係る光デイスクの反射率測定
装置の一実施例を示す構成図、第２図は各部の動
作波形図である。１……コンパレータ、２……レベル変換器、３
……ダウンカウンタ、４……ラツチ、５……ＣＰ
Ｕ、６……ＤＡ変換器、７……ローパスフイルタ
、８……サンプルホールド回路、９……ＡＤ変換
器、１０……単安定マルチバイブレータ。 FIG. 1 is a block diagram showing an embodiment of an optical disk reflectance measuring device according to the present invention, and FIG. 2 is an operational waveform diagram of each part. 1...Comparator, 2...Level converter, 3
...Down counter, 4...Latch, 5...CP
U, 6...DA converter, 7...Low pass filter, 8...Sample hold circuit, 9...AD converter, 10...Monostable multivibrator.

Claims

[Claim for Utility Model Registration] A comparator that compares a signal proportional to the reflectance of the optical disk with a threshold value and generates a pulse at the starting point of the preformat section, and a comparator that receives a signal proportional to the reflectance of the optical disk. a low-pass filter that passes only the fundamental wave component of the signal from the preformat section; a sample-and-hold circuit that samples and holds the output of this low-pass filter; and a signal that puts the sample-and-hold circuit into a hold mode for a certain period of time from the output edge of the comparator. and a monostable multivibrator that generates a monostable multivibrator, wherein a reflected wave signal from which a signal from a preformat section has been removed can be obtained from the sample and hold circuit.