Low-cost hand-held probe for depth-resolved low-coherence interferometry

Abstract

We report on the development of a low-cost hand-held low-coherence interferometric imaging system based on the principle of linear optical coherence tomography (Linear OCT), a technique which was first proposed in the early 2000s as a simpler alternative to the conventional time-domain and Fourier-domain OCT. A bench-top implementation of the proposed technique is first presented and validated. The axial resolution, SNR, and sensitivity roll-of of the system was estimated to be 5.2 µm and 80 dB, and 3.7 dB over a depth of 0.15 mm, respectively. After validating the bench-top system, two hand-held probe implementations for contact-based imaging and in vivo human tympanic membrane imaging are presented. The performance of the proposed system was compared with a research-grade state-of-the-art Fourier-domain low coherence interferometry (LCI) system by imaging several biological and non-biological samples. The results of this study suggest that the proposed system might be a suitable choice for applications where imaging depth and SNR can be traded for lower cost and simpler optical design.

Economical and compact briefcase spectral-domain optical coherence tomography system for primary care and point-of-care applications

“…Our developed system demonstrated a higher line rate of 10 kHz, which is higher than the reported low-cost TD-OCT technology. 20,37 In these terms, the use of FD-OCT technology opens a broad range of options for low-cost OCT systems. Researchers globally are striving to miniaturize SD-OCT and SS-OCT on a silicon chip.…”

“…Globally, researchers are developing cost-effective and mobile OCT systems based on both TD-OCT and FD-OCT platforms with unique detection/illumination schemes. Previous reports demonstrated the development of a compact platform within a handheld low-coherence interferometry (LCI) system, 20 and a multiple reference (MR) OCT system. [21][22][23] The handheld LCI system used for in vivo ear imaging was based on a linear OCT approach, 20 and the overall cost to develop this system was significantly lower than most other FD-OCT systems.…”

“…Previous reports demonstrated the development of a compact platform within a handheld low-coherence interferometry (LCI) system, 20 and a multiple reference (MR) OCT system. [21][22][23] The handheld LCI system used for in vivo ear imaging was based on a linear OCT approach, 20 and the overall cost to develop this system was significantly lower than most other FD-OCT systems. MR-OCT, another low-cost OCT approach, was developed based on a partial mirror and actuator configuration, generating a recirculating optical delay line.…”

Design and implementation of a low-cost, portable OCT system

“…However, the OCT system engines of these systems (which include the light source, spectrometer, PC, and interferometer optics) are still bulky and expensive which limit application of these systems for point of care imaging. Recent efforts in developing a comprehensive low-cost OCT system include a miniaturized, low-cost, fully packaged silicon photonic integrated swept-source OCT [11] and a low-cost handheld linear OCT that could be built using only standard off-the-shelf inexpensive components [12]. However, reductions in size and cost of these systems come with a significant sacrifice of SNR and reduced imaging depth.…”

Image processing methods for computer-aided screening for disease

“…OCT is an image modality expanding in dermatology, as we described before, it is a valuable aid in the detection and monitoring of skin lesions but its high prize compared to dermoscopy, limits their use in screening and early detection. The use of portable handheld low-cost probes can improve the adoption of this technology and increase their use in primary care as has been already presented in recent studies (Shelton et al 2014;Pande et al 2017).…”