High-speed En Face Optical Coherence Tomography  Measurement System Developed

High-speed En Face Optical Coherence Tomography Measurement System Developed

Will be used for analysis for diagnosing skin disorders relating to sweating, ophthalmic diagnosis, and other research applications

Apr 20, 2015

A group of researchers led by OHMI Masato (Professor, Graduate School of Medicine, Osaka University) succeeded in developing a high-speed en face optical coherence tomography measurement system (en face OCT) that uses a function as optical deflector of crystals of potassium tantalate niobate (KTN). KTN crystal is expected to be used for optical deflectors and variable focusing lens developed by the Nippon Telegraph and Telephone Public Corporation (NTT).


Optical coherence tomography (OCT) is an established medical imaging technique that uses light to capture micrometer-resolution, three-dimensional (3D) images from within the biological tissue. The KTN crystal has a very large electro-optic (EO) effect, which changes its refractive index when a voltage is applied and bends the path of a light beam in a new direction. The deflection effect of the KTN exhibits a fast response of up to several hundred KHz and a fairly large light deflection angle. Considering this performance, we proposed a novel high-speed en face OCT system that used a KTN optical deflector as the sample probe. As a preliminary experiment, we have succeeded in obtaining en face OCT images of human fingerprint with a frame rate of 500 fps. This is the highest speed obtained using time domain en face OCT imaging in the world. Our development permits in vivo real-time imaging with fewer motion artifacts including 3D imaging of the object and this technique will lead to useful clinical applications.

This group's achievement was presented at the OPTICS & PHOTONICS International Conference (OPIC 2015) that was held from April 22 through April 24, 2015.

Figure 1. KTN optical beam deflector

Figure 2. The schematic of the high-speed en face OCT system

Figure 3. Scanning method for en face OCT imaging and acquisition of 3D-OCT data

Figure 4. En face OCT and 3D-OCT images of human fingerprint. (a) En face OCT image of x-y plane and 2D-OCT image of x-z plane, (b) Constructed 3D-OCT image

To learn more about this research, please view the full research report entitled " Development of novel high-speed en face optical coherence tomography system using KTN optical beam deflector " at this page of the IOP Science website.

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