发明名称 |
SEMICONDUCTOR LASER DRIVE APPARATUS, OPTICAL WRITE APPARATUS, IMAGING APPARATUS, AND SEMICONDUCTOR LASER DRIVE METHOD |
摘要 |
A semiconductor laser drive apparatus and method are disclosed in order to obtain an optimal laser emission pulse that can reduce inherent light emission that may cause fogging and degradation of a photoconductor and also reduce turn on delay. Specifically, a light emission command signal is delayed at a delay unit based on a delay control signal so that a modulation signal is output. The light emission command signal and the delay signal are logically added to a command signal from an external source at a threshold signal generation unit so that a threshold ON signal is output. The modulation signal and the threshold ON signal respectively drive a modulation current switch and a threshold current switch so that a semiconductor laser drive current is generated. The threshold current is sampled according to a sample hold signal supplied from an external source and APC is performed on the sampled threshold current. In a differential quantum efficiency detection unit, an operation of determining differential quantum efficiency based on a current for obtaining a predetermined amount of light and a current for obtaining a portion of the predetermined amount of light is performed, and a light emission current is calculated. By adding the calculated light emission current and an arbitrary current that may be externally set, a modulation current for switching the semiconductor laser can be obtained.
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申请公布号 |
US2008002747(A1) |
申请公布日期 |
2008.01.03 |
申请号 |
US20070854169 |
申请日期 |
2007.09.12 |
申请人 |
ONO KENICHI |
发明人 |
ONO KENICHI |
分类号 |
B41J2/44;H01S5/06;H01L31/072;H01S5/042;H01S5/062;H01S5/068;H01S5/0683;H01S5/50;H04N1/036;H04N1/113 |
主分类号 |
B41J2/44 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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