KTN-based electro-optic beam scanner

Abstract

We report a new type of high-speed electro-optic (E-O) beam scanner based on Potassium Tantalate Niobate (KTN) crystal. It has larger scanning angle, better angular resolution, and lower driving voltage comparing to the traditional E-O crystal beam scanner. Compared to conventional moving mirrors such as servo-controlled mirrors and galvanic mirrors, the demonstrated E-O beam scanner can improve the response time by 100 times. The presented device has many other unique features such as light weight, small dimension, low power consumption, and no-moving components particularly suitable for airborne and space-borne applications.

Anomalous laser deflection phenomenon based on the interaction of electro-optic and graded refractivity effects in Cu-doped KTa1−xNbxO3 crystal

“…Most traditional scanners are mechanically based, such as galvanic mirrors and micro-electromechanical scanners with moving parts, which are relatively slow and are subject to wear and eventual damage. 1 When compared with conventional laser scanning technologies, electro-optic laser scanning has numerous advantages, including small size, fast response, and inertia-free performance, and thus, electrooptic laser scanning technology has broad application prospects in high-tech fields such as laser radar, laser ranging, and microscopic imaging. 2 Because of their small electrooptic coefficients, traditional electro-optic laser scanner materials, such as LiNbO 3 and KH 2 PO 4 prisms, need very high driving voltages to obtain practical deflection angles, while potassium tantalate niobate (KTa 1Àx Nb x O 3 , KTN) crystal electro-optic beam scanners, thanks to their excellent quadratic electro-optic effect, can achieve large deflection angles with relatively small driving voltages.…”

Growth and Laser Modulation Properties of KTa0.63Nb0.37O3 Single Crystals

“…In 2007, Nakamura reported the achievement of large angle and low-voltage electro-optic beam scanning using KTN crystal [3]. In 2008, Tang et al also reported a high-speed electro-optic beam scanner based on KTN crystal [4]. In 2012, Okabe et al presented a new light source for swept-source optical coherence tomography (SS-OCT) using a KTN electrooptic deflector [5].…”

Two-dimensional beam-steering device using a doubly periodic Si photonic-crystal waveguide

“…Conventional optical deflectors are mechanical devices that use the rotation of the device itself or a deflecting mirror, and they have problems such as large size, high cost of assembly, and instability to vibrations of the moving body [1]. Microelectromechanical systems (MEMS) [2], electro-optic effects [3], phase-change materials [4], acousto-optic effects [5], and liquid crystals [6] have also been studied, but their small deflection angles, large beam divergence, and/or slow response speeds are still problems. Recently, the development of nonmechanical optical deflectors fabricated using silicon (Si) photonics technology has become an active area of study.…”