Research for miniaturization and portability of optical coherence tomography, which has received considerable attention as one of the pre-diagnosis methods, has been conducted for several years to further expand the utility of optical coherence tomography. In this study, we introduce a method that can dramatically reduce the size of a system and resources using a Raspberry Pi miniature computer and the proposed small spectrometer. The optical systems of the sample stage and the reference stage were configured as half-inch optical components to reduce the size of the system. The size of the sample stage was minimized by using a MEMS scanning mirror. We designed a board that converts the unipolar drive signal into a bipolar signal to drive the MEMS scanning mirror with Raspberry Pi. The MEMS mirror was controlled by a commercial AD/DA conversion board and a developed board that can be controlled via the general-purpose input-output (GPIO) pin of Raspberry Pi. Furthermore, we also designed the spectrometer to fit the 1-inch optical system. The camera was selected as a product that can supply power and transmit data through the USB terminal to operate all other components, including the camera, through a portable charger. Due to camera performance limitations, A-scan 5 kHz was the maximum speed, but the resolution was axial 8.5 μm (Air) and lateral 17.54 μm, showing similar performance to a commercial system. Although the operating speed is slow, it is expected to be used in various fields due to its portability advantage.
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