LCoS光源选型终极指南：LED与激光的对决

Core Viewpoint - The article discusses the selection of LCoS lighting sources and the design criteria for LCoS lighting paths in AR glasses, comparing the differences between using LED and laser as lighting sources [1][4][22]. Group 1: LCoS Technology Overview - LCoS (Liquid-Crystal-on-Silicon) utilizes liquid crystals to modulate light, similar to LCD technology, but offers advantages such as higher energy efficiency, resolution, contrast, and color richness, making it suitable for high-end projection devices and AR/VR headsets [3][4]. - In the AR glasses industry, LCoS has become a mainstream choice due to its mature technology and low cost, with several companies adopting LCoS display sources combined with waveguide technology [4][22]. Group 2: Lighting Source Comparison - The current LCoS lighting modules primarily consist of LED and laser sources. LED sources are reliable and cost-effective but have limitations in brightness due to their hemispherical emission pattern, making them unsuitable for bright environments [6][22]. - Laser sources, while more expensive and requiring advanced cooling systems, offer advantages such as strong directionality, high brightness, and better color saturation, making them more suitable for outdoor use and high-brightness applications [22][25]. Group 3: Optical Design Considerations - From an optical design perspective, lasers have a smaller emission angle compared to LEDs, allowing for easier beam manipulation and a more compact optical system [11][14][20]. - The energy utilization efficiency of laser sources is higher due to their ability to couple more effectively into waveguides, reducing the risk of stray light that can interfere with image display [16][20]. Group 4: Image Quality and Challenges - LCoS technology benefits from high-power density laser sources, which significantly enhance brightness and color saturation, surpassing LED capabilities [21][22]. - However, challenges such as speckle noise caused by coherent laser light and the high thermal demands of laser systems pose significant barriers to widespread adoption [22][23]. Group 5: Recommendations - For indoor applications with lower brightness requirements, LED sources are recommended, while laser sources are better suited for outdoor scenarios where high brightness and color fidelity are essential [25].