摘要
用两片高速A/D转换器和一片闪速存储器(Flash ROM)构建了高分辨率和高频响的莫尔条纹信号细分电路。光栅信号经A/D转换后只需访问一次只读存储器即可输出细分值。通过修改只读存储器的写入数据,可方便地实现不同的细分倍数。在100倍细分时能够实时处理50kHz的输入信号,最高可处理1MHz的信号。实现了光栅信号高频响和高细分处理的统一。通过计算实际信号与理想信号的数量积的方法分析了直流漂移、非正交误差、等幅性误差和三次谐波对只读存储器细分的影响。为进行误差修正和误差补偿奠定了基础。
A high speed and high resolution subdivision method is realized by using two high speed A/D convertors and a flash ROM. Subdivision data is obtained by reading ROM one time only after A/D conversion. The division numbers can be changed conveniently by programming ROM. It can real-time process when the signal frequency is 50kHz with 100 divisions. It can process the signal frequency up to 1MHz, so it has the advantages of both high response speed and high division number. The influence of zero offsets, quadrature phase shift error, unequal amplitude in the two channels and third harmonic on subdivision accuracy is analyzed by calculating quantitative product of actual signal vector and idea signal vector.
出处
《光学技术》
EI
CAS
CSCD
北大核心
2008年第5期738-741,745,共5页
Optical Technique
关键词
光学测量
莫尔条纹
细分
高频响
误差分析
optical measurement
moire fringe
subdivision
high response speed
error analysis
