Axial-lateral parallel time domain OCT with optical zoom lens and high order diffracted lights for variable imaging range.
We developed a method to adjust measurement range within axial-lateral parallel time-domain optical coherence tomography (ALP TD-OCT) using an optical zoom lens and high-order diffracted lights. A two-dimensional (2-D) camera can produce a depth-resolved interference image using diffracted light as the reference beam and a linear illumination beam without axial and lateral scans. The lateral range can be varied continuously from 4 to 8 mm using an optical zoom lens. Axial range could be adjusted discretely by 1st, 2nd, 3rd, and 4th orders because we used reflective diffraction grating with 300 lines/mm in a 1.3 mum wavelength region. OCT images (320 x 256 pixels) can be displayed at 30 frames second (fps) by calculating two interference images, captured by an InGaAs camera operated at 60 fps. With a 1.05-ms exposure, the ALP TD-OCT system has sufficient sensitivity (94.6 dB) to image the human finger in vivo.
Watanabe
Yuuki
Y
Graduate School of Science and Engineering, Yamagata University, 4-3-16 Johnan, Yonezawa, Yamagata, 992-8510, Japan. ywata@yz.yamagata-u.ac.jp
Takasugi
Yasutoki
Y
Yamada
Kazuhiko
K
Sato
Manabu
M