The VDL-001 from Luna Innovations is a manual Variable Optical Delay Line (ODL) that operates at wavelengths of 840, 1060, 1310 or 1550 (polarization mode single pass), 1310/1550 (dual window), 1060, or 840nm (single-mode single pass) and 1310 or 1550nm (single-mode double pass). It has an optical delay range of 0 - 600 ps (single pass) and 0 - 1200 ps (double pass). This fiber-coupled ODL has an insertion loss of 1 - 1.5 dB (single pass) & 1.5 dB (double pass), and a return loss of 50 dB. It has a readout scale resolution of 0.05 mm and an extinction ratio of over 18 dB for polarization mode. This ODL has a polarization-dependent loss of 0.1 - 0.2 dB for single-mode fiber.
The VDL-001 has a delay adjustment path in free space whose delay is adjusted by manually turning a handle on one end of the device, and the position is read from a vernier scale on the side. It is available in a compact module that measures 4.2 x 2.1 x 1 inches (330 ps model) or 6 x 2.1 x 1 inches (600 or 1200 ps model) with HI780 or PM Panda (for 840 nm), HI1060 or PM Panda (for 1060 nm) and SMF-28 fiber. This ODL is ideal for optical coherence tomography (OCT) systems, passive time division multiplexing, TDM bit alignment, and fiber interferometer applications.