Light emitting diode arrays for consumer and medical applications

Development of light emitting diodes (LEDs) and arrays of diodes to be utilized in a modern and highly sensitive spectrophotometer is presented. The In1−xGaxAs1−yPy quaternary alloy semiconductor has been utilized in the design and fabrication of surface emitting infrared LEDs in the spectral range from 1100 to 1650 nm. Custom made chips provide the surface-emitting LEDs with high radiance and superior far-field patterns. The hybrid 31-element array of LEDs was fabricated. A temperature sensor and a photodiode was incorporated on the hybrid circuit to control the temperature and light intensity of the diodes. The instrument prototype has been fabricated and preliminary experimental data have been collected.