Focuslight technologies, a global provider of high power diode lasers and micro optics, has announced the LIMO Wide Angle Diffuser at SPIE Photonics West 2020. Designed for automotive LiDAR and 3D sensing applications, the LIMO Wide Angle Diffuser is a glass refractive optical element (ROE) with the ability to disperse laser light in one direction up to a full illumination angle, ranging from a few mrad up to 150 degrees. When combined with a second functional surface, the light can also be shaped at any desired angle in the other direction. This makes it possible to obtain a rectangular field with a steep edge slope and a user-defined field of view (FOV), for example 60° x 45° or 120° x 25°. The Wide Angle Diffuser is designed to work with a variety of light sources, including collimated light, diverging light, or a light source array, such as VCSELs.
"For high-precision detection of distances between vehicles and their static and dynamic environment, the laser beam must be shaped into a light field with a defined field of view," said Kenneth Ferree, VP of Sales and Marketing at Focuslight Technologies. "Thanks to its zero hot spot beam shaping, the new LIMO Wide Angle Diffuser delivers consistent performance, even in extreme operating temperatures. Its expansive illumination area enables full coverage of the 360° surrounding view with just four LiDAR systems for reliable driving safety."
Unlike diffractive optical elements (DOE), which are limited to small angles, moderate ambient conditions, and have an intensity distribution that drops flat at the edges, the LIMO Wide Angle Diffuser is an eye-safe ROE with no zero-order and no "hot spot." The glass material features small refractive index variation and small thermal expansion with temperature, delivering stable performance over a wide temperature range (-40 °C~150 °C). High uniformity and high window efficiency within the FOV deliver a homogenous intensity profile in angular space with high-quality edges. The end result is high efficiency that allows intelligent use of every generated photon while preventing scattered radiation.