激光全息照相景深扩展实验探讨

Expansion of the depth of field in holography experiment

对于具有较大景深的物体,全息照相常常不能一次得到全部清晰的物像,即在物像上局部模糊甚至出现暗区,其主要原因是物体的景深超出了激光器的相干长度所能允许的最大景深限度.利用光程补偿的方法,借以达到扩展全息照相景深的目的,使之在激光器的相干长度范围内.

Usually, for objects of large depth of field, an all-clear image could not be obtained in one holography experiment, i. e. , the image had vague field or dark field. The reason was that the depth of field of the object exceeded the maximum depth of field according to the coherence length of laser. In order to expand the depth of field of laser, the method of compensating optical path was in- troduced to obtain the clear image.