Spectrometer Design for an 840 nm Spectral Domain Optical Coherence Tomography System

In this paper, the design and performance of a custom-built spectrometer for Spectral Domain Optical Coherence Tomography (SD-OCT) imaging for a near-infrared wavelength range centered around 840 nm is presented. Two configurations of spectrometers based on reflective and transmission type grating and achromatic doublet lens were analyzed and the spectrometer performance characteristics are studied. The spectrometer is designed to work best with a light source whose wavelength is 840 ± 46 nm. A line scan camera captures multiple wavelengths simultaneously. In order to achieve higher resolution and imaging depth, a 2048-pixel array linear line scan camera from Basler was chosen. The line scan camera’s detector has a length and width of 14.3 mm and 7 μm, respectively. The spectrometer design was simulated using Zemax software and the design parameters are described in this paper.