Single Mode Laser Diodes ROHM Semiconductor Single Mode Laser Diodes are available in wavelengths that range from 635nm-850nm with the industry standard of φ5.6 metal stem. These diodes are used in applications such as optical disk pickup and sensor. The single-mode laser diodes use tray packaging and are RoHS compliant. The single-mode laser diode is available as infrared laser diodes and red single-mode laser diodes. Typical applications include optical disk pickup and sensor.