Light sources used in OCT generally have a short coherence length. In order to obtain an interference signal, it is necessary to make the optical path length difference between the sample optical path and the reference optical path as close as possible. On the other hand, when constructing an interferometer by combining fiber components, It is very difficult to precisely control the fiber length difference (optical path length difference) between the sample optical path and the reference optical path.
Therefore, an optical path length variable mechanism (delay line) having a relatively large variable amount for adjusting the optical path length is usually required.
This results in larger systems, higher costs, and unstable performance.
We use our experiences and technology gained from designing and manufacturing many different types of fiber interferometers. Our products are highly praised from our customers by minimizing the problems.
With our modules, interference signals can be easily obtained only by fine-tuning the delay line with a small variable distance built into the sample optical system or reference optical system. If you are building a complicated fiber interferometer with the most advanced OCT research and are having a hard time adjusting the optical path length, or if you are having difficulty adjusting the optical path length in the production process of mass-produced products, please contact us once by all means.

Considering the stability of OCT sensitivity, it is important to stabilize the SOP due to changes in environmental temperature.
Optical fiber couplers made by other companies had the problem that the sensitivity of OCT fluctuated because the SOP greatly changed with temperature.
Therefore, in order to solve this problem, we have developed a unique and highly reliable optical fiber coupler for OCT applications that minimizes the fluctuation of the SOP due to temperature changes.
The graph below shows how the polarization state changes over time when the temperature is changed between 5 and 75°C. Compared to other companies' optical fibers, the fluctuation of the SOP with respect to temperature is greatly suppressed, indicating that it is extremely stable. At present, this optical fiber coupler is used by many companies and universities that conduct R&D and manufacturing of OCT, and the results have been reported (Reference 1). *Reference1： Shinnosuke Azuma,Yoshiaki Yasuno et al. Clinical multi-functional OCT for retinal imaging Biomedical Optics Express(2019)