The Sharp LT023PS is a GaAlAs laser diode with VSIS chip structure. It has a built in photo diode for monitoring the laser output for use in automatic power control (APC) circuits. The common case pin is laser diode cathode and photo diode anode.
These are new old stock diodes, individually characterized in factory containers.
Specifications:
Output Power: 3.0mW typical, 5.0mW maximum
Wavelength: 780nm typical, 795nm maximum, INFRARED
Operating Voltage: 1.75 Volts typical
Threshold Current: 45mA typical
Operating Current: 55mA typical
Monitor Current: 0.4mA typical
Operating Temperature: -10 to 70 deg.C
Package: TO-18, 5.6mm diameter base
Factory spec sheet found HERE
Note: Due to the sensitive nature of laser diodes, there is no warranty or exchanges on these items.