Coherent diffraction imaging device and method based on low dynamic range spectrogram

Abstract

The invention provides a coherent diffraction imaging device and method based on a low dynamic range spectrogram, and the device comprises: a light source module which is used for generating a beam of monochromatic parallel light to provide a light source for a to-be-detected sample; a modulation module which is used for loading n coding patterns to modulate the to-be-detected sample so as to obtain n low dynamic range spectrograms corresponding to different parts of the to-be-detected sample, wherein n is an integer greater than 2; an image acquisition module which comprises an acquisition lens and a camera which are sequentially arranged in the optical axis direction, wherein the sample plane of the to-be-detected sample is strictly located on the imaging front focal plane of the acquisition lens due to the arrangement position of the acquisition lens, and the n low-dynamic-range spectrograms are acquired through the camera; and a data processing module which is used for calculating the n collected low-dynamic-range spectrograms through a self-adaptive iteration phase retrieval algorithm to obtain the complex amplitude of the to-be-detected sample. The problem that a conventional coherent diffraction imaging technology needs to collect a high-dynamic-range and low-dynamic-range spectrogram to ensure the recovery precision is solved.

Description

technical field [0001] The invention belongs to the field of optics, and in particular relates to a coherent diffraction imaging device and method based on a low dynamic range spectrogram. Background technique [0002] Phase recovery is a technology that measures the intensity distribution of the light field and then numerically calculates the phase distribution of the light field. It is widely used due to the advantages of low construction cost, simple operation and strong anti-interference ability of the measurement device. Coherent diffraction imaging technology is one of the most commonly used kind of. However, the general coherent diffraction imaging technology has higher requirements on the dynamic range of the low dynamic range spectrogram in order to ensure higher imaging accuracy, which puts forward higher requirements on the bit depth of the acquisition camera (usually above 13 bits), otherwise It is necessary to use multiple images to synthesize a high dynamic ra...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the embodiments of the present invention is to provide a coherent diffraction imaging device and method based on a low dynamic range spectrogram to solve the problem that conventional coherent diffraction imaging technology needs to collect a high dynamic range and low dynamic range spectrogram to ensure the recovery accuracy, resulting in the collection of patterns Complicated and time-consuming operations or high requirements for camera bit depth

Images