Advanced Photonix, Inc. (API) is a leading supplier of optoelectronic solutions and terahertz sensor instrumentation. The company was founded with a vision to leverage patented photodiode technologies for high-speed optical sensing. Its headquarters are located in Ann Arbor, Michigan, with additional design and manufacturing facilities in California. API's core business revolves around the design and manufacture of custom photodiodes, optical receivers, and terahertz systems for OEM customers worldwide. The product portfolio includes large-area silicon avalanche photodiodes (LAAPD), high-speed InGaAs photodetectors in APD and PIN configurations, and the patented FILTRODE® detector technology. These components serve a broad range of applications such as medical diagnostics, military guidance, industrial laser control, and optical communications. In the terahertz segment, the T-Gauge® sensor platform enables non-destructive testing for material characterization, baggage scanning, and quality control. The company's innovation is backed by numerous patents covering III-V material photodiodes and advanced packaging techniques. API has established a strong market presence as a preferred partner for critical optoelectronic and terahertz sensing solutions. In 2015, Advanced Photonix was acquired by Luna Innovations, expanding its capabilities in fiber optic sensing and test systems.