Free Field of View Infrared Digital Holography for Mineral Crystallization

Abstract

Investigating the crystallization process is a crucial approach for understanding crystal properties. However, traditional optical microscopy and infrared spectroscopy often fail to capture essential information, particularly during the crystallization behavior, due to common limitations in the field of view and the inability to obtain phase features. To address these challenges, a novel approach is proposed that combines a free field of view scheme with infrared holographic detection for dynamic crystal observation. This configuration enables the acquisition of phase attributes of targets in a field of view. We analyze the issue of displacement errors in reconstruction and overcome it by employing a subpixel displacement registration and intensity calibration algorithm. Experimental verification demonstrates that the present approach can not only be applied to the study of crystallization processes but also enables the amplitude and phase characteristics of steady resolution targets, artificial samples, natural objects, and minerals in the infrared band. Infrared digital holography using the free field of view, ranging from 1.2 million pixels to 55 million pixels, is expected to be a promising technical tool in the research of crystallography and mineral materials identification, especially in the blind spot of traditional detection techniques, where more detailed properties can be obtained through phase information.

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