| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect a desired voltage level for carrying out proper negative feedback control by emitting a laser beam at predetermined emission power, for example, even when the emission power of the laser beam is switched at high speed. <P>SOLUTION: A voltage level detector (100) for detecting a desired predetermined voltage level in a voltage signal whose voltage level changes stepwise to a binary level or more (Vp or Vb), is provided with a peak holding circuit (200) having holding time (HT) set so that the voltage level of a voltage signal at the end of peak hold becomes a predetermined voltage level, and a bottom holding circuit (300) having hold time set so that the voltage level of the voltage signal at the end of bottom hold becomes a predetermined voltage level in the case of a change to a high voltage level side. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
