This PDF file contains the front matter associated with SPIE Proceedings Volume 12014, including the Title Page, Copyright information, Table of Contents and Conference Committee lists.

The recent development of the MEMS Phase Light Modulator (PLM) enables fast laser beam steering for lidar applications by displaying Computer Generated Hologram (CGH) on-the-fly without resorting to iterative CGH calculation algorithm. We discuss application of MEMS PLM (Texas Instruments PLM) for quasi continuous laser beam steering by deterministically calculated CGHs.

Laser beam steering is an essential function for LiDAR. Phase Spatial Light Modulator (SLM) provides a capability of steering beam in a fast and random-access manner but suffers from limited FOV and side lobes. In this paper, we present a DMD (Digital Micromirror Device)-PLM hybrid beam steering concept that features high resolution, large-FOV, and side-lobe free beam steering.

We developed a novel spectrum simulating light source that uses a high brightness Laser-Driven Light Source (LDLS) and high throughput, spectrally programable light engine to deliver high fidelity spectrum matching between 380 nm and 780 nm. The light source leverages the tunability of a digital micromirror device (DMD) with characterization algorithms to produce open-loop spectral matched light output. A monitoring spectrometer is not necessary for matching preloaded target spectra after an initial characterization of the system transfer function. The reported light source can match spectral lines down to 4.5 nm full-width-half-maximum (FWHM) linewidth and simulate the detailed spectral profiles of compact fluorescent lamps with high fidelity. With a 380 nm to 780 nm wavelength range, the source can be a valuable tool for sensor calibration, hyperspectral imaging, and medical-related research.

The Digital Micromirror Device (DMD), developed by Texas Instruments (TI), has been in production for over 25 years. It is a Micro-optical-electro-mechanical system (MOEMS) that functions as a spatial light modulator (SLM) by directing millions of points of light into or out of the projection optics path. TI is now developing a new MOEMS device based on the same processes, equipment sets, and design knowledge as the DMD. This new device operates in a piston mode with each mirror moving up and down instead of rotating left and right as the DMD does. By operating in a piston mode, the mirrors can modulate the phase of light and function as a phase light modulator (PLM). This paper focuses on the reliability of the PLM device. TI has a strong foundation for MOEMS reliability resulting in the mature and reliable DMD. Early results from various life tests and environmental tests confirm that PLM reliability is comparable to DMD reliability. The paper will discuss reliability test results and related performance metrics.

Most of smart headlight engines are designed using blue LED or laser light sources for the exciting the phosphor conversion layer producing white light output. The phosphor conversion layers have been fabricated by silicone-based phosphor, glass-based phosphor, ceramic-based phosphor, and single crystal-based phosphor. Among these different phosphor materials, the single crystal phosphor (SCP) exhibits excellent thermal stability, better conversion efficiency, and high transparency to yellow light, but the required high-temperature fabrication process, has been an impediment for widespread commercial production. Recently, the issues of higher fabrication temperature of the SCP have been overcome by using a novel design of single crystal growth to produce SCP with higher yield and better uniformity. In this study, the smart headlight consists of a well-developed, high efficiency, automotive qualified white LED, a TI digit mirror device (DMD), a projection lens, and a LED together with two laser diodes and a SCP plate.

By combining a Micro Electro Mechanical System based resonant mirror and a Digital Micromirror Device, we demonstrated a large scan angle, fast scan rate, and high resolution beam steering for the lidar applications. The proposed optical architecture preserves a large Etendue of DMD-based diffractive beam steering with a synchronized short pulsed laser to transition of micromirror array while increasing angular resolution.

CUDA-OpenGL interoperability enables to drastically reduce the computational time for CGH calculation and display on Spatial Light Modulators via HDMI display channel. The fast calculation method enables on-the-fly diffractive beam steering by Micro Electro Mechanical System based phase light modulator with YOLOv4-tiny model based object recognition to do AI-based dynamic beam tracking in order to trace the object of interest.

We present a 3D electromagnetic simulation of a digital micromirror device (DMD) from 0.4 µm to 5 µm, which accurately models DMD reflectance and contrast ratio, including the effects of diffraction. A DMD is a spatial light modulator with a wide range of applications, including projection displays, 3D printing, and imaging spectroscopy. The physical structure of the DMD induces strong wavelength-dependent diffraction effects that impact the stray light, optical throughput, and pupil illumination distribution of a system. To quantify this, we perform a 3-dimensional electromagnetic finite-difference time-domain simulation, illuminating the DMD with a focused, incoherent beam, explicitly calculating the near-field electric fields, and calculating the far-field distribution of light. The far-field data determines diffraction efficiency and the distribution of light across the pupil. With these models, we are able to study the DMD’s optical efficiency in three key regimes: the specular regime, where the DMD behaves like a segmented mirror with a diffractive component (λ < 1 µm); the diffraction-dominated regime, which is also described by analytic diffraction grating theory (3 µm < λ < 5 µm); and, uniquely, the transition region, where the specular reflection and diffraction contributions are comparable (1 µm < λ < 3 µm). Our results inform system performance parameters, provide optical design constraints, and create a framework of use cases for DMDs.

By employing Talbot self-imaging, phase modulation depth of a Spatial Light Modulator (SLM) is doubled without employing relay optics and/or multiple SLMs. The proposed optical architecture enables laser beam steering of infrared light with enhanced diffraction efficiency while using a single SLM designed for visible wavelength.