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Laser excited phosphor wheel light source has an upper output power limit due to the issues in heat dissipation and the high-power density at the focus on the phosphor. This paper presents a stationary phosphor plate with a compact rotating optical system such that the focused laser spot on the phosphor plate follows a circular path providing a larger effective excitation area while maintain the small etendue of a single stationary focused spot. With an 8 mm diameter circular path, a theoretical total of 1,870 W of laser power focused into a 2 mm spot can produce a total 500,000 lumens of visible light. This will make a 120,000 screen-lumen projector possible.

Besides low cost, automobile design will be another major factor for the mass adoption of the LiDAR in the autonomous vehicles. Extra aperture in the automobile chassis for LiDAR operation will be undesirable for automobile designers. As a result, it will be advantageous to integrate the LiDAR together with the headlight such that the chassis design of the vehicle does not have to deviate from standard practices. This paper presents optical design of integrated LiDAR and smart headlight using a single DMD such that it replaces the current headlight without impact on the overall chassis design of the vehicle. For low cost considerations, the two functions share the same DMD. Preliminary designs of such system and results will be presented.

Automotive headlight evolved from incandescent, to halogen, to xenon, to LED, and most recently, to laser phosphor lamps with increasing efficiencies and brightness. This paper presents the development of laser phosphor headlights using glass phosphor and single crystal phosphor for efficient and high power operations. Laser diodes are used for pumping the phosphors producing the white light to be projected to the roadway. In addition, various configurations of the laser diodes, which are individual addressable, are to be presented. Together with the used of DLP and LCD imagers, intelligent headlights are developed with the abilities selectively scanning the imagers illuminating the roadway with varying intensities. The design of the systems and the experimental results will be presented.

The most widely used light sources for projection system and spotlights are discharge lamps. With tremendous advancements over the last decade in blue laser developments, laser excited phosphor systems have been developed for various applications including projectors and spotlights. One major challenge remains in the very high power applications where multi-kilowatt xenon lamps are still being used. In this paper, an advance material, namely, single crystal phosphor has been developed with high optical efficiency, high power handling capability, and a melting point of 1,950°C. To enable such single crystal phosphor to be used to its full capacity, a major effort was placed on the heat sinking of the crystal phosphor pumped at high power, over 70 W of blue laser power from a 4 by 6 array of laser diodes. The nominal dimension of the crystal phosphor of one of the system measures 2 mm by 2 mm by 4 mm and is end-pumped from one end with a set of focusing lenses directing the output from 24 lasers onto the surface of the crystal phosphor. The 4 sides of the crystal phosphor is specially coated and attached to the heat sink for efficient dissipation of heat, keeping the temperature of the crystal low enough for efficient emission. The output from the crystal phosphor is extracted using a CPC reducing the total internal reflection effect inside the crystal phosphor. To accommodate the high power laser at the input face of the crystal phosphor, various methods are used to prevent the local burning of the input face, including the use of diffusers, light pipes, and light tunnels. The computer simulation and experimental results will be presented.

Traditional illumination systems uses various lamps selected based on certain requirements of the applications. One common issue is the trade-off between output brightness and lamp lifetime. LEDs with long lifetimes have been used in many applications. This paper describes a multi-colored LED illumination system with individually controlled red, green, and blue outputs combined together with the etendue of a single LED, having enhanced green and red output brightness with supplementary excitation of the phosphor-based green and red LEDs from additional blue LEDs, increasing the overall output of the system.

As the minimum feature size shrinks to 130nm region, attenuated phase shift mask (attPSM) with optical proximity correction (OPC) is reportedly as one of the potential methods to achieve manufacturable process by using 248nm exposure wavelength. For a typical mask making process, sometimes it is necessary to perform mask repairs to remove unwanted defects. Repairing either the OPC features or the attenuated phase-shifting main features present a new challenge in the mask making process. For both clear and opaque types of imperfect repairs, the repaired edge placement accuracy and/or transmission and phase shirt matching after repair may cause considerable amount of changes in the aerial images and then be transferred into resist patterns. Some imperfect repairs may become killer defects while others can significantly reduce the lithography process latitude, especially around the forbidden pitches. In our study, the effectiveness of defect repairs for 130nm gate attPSM at different pitches is assessed by direct examination from printed wafers.