This part is a kind of semiconductor called ADL-78901SX.

Function of this product has Laser Diode.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

AlGaAs Infrared Laser Diode ADL-78901SX 3.3mm Mini Package! 200mW High Power Reliable Operation • Features 1. Smallest package 2. Low operating current 3. Small aspect ratio 4. High COD level • Applications 1. Virtual keyboard 2. Super slim 40X CD-R/RW OPU • Absolute maximum ratings Parameter Symbol Condition Light output power PO CW Pop Pulsed* Reverse voltage(LD) Case temperature Storage temperature VRL TC TS - * Pulse width 0.5us, duty cycle 50% Rating 100 220 2 -10~+70 -40~+85 Unit mW V oC oC • Electrical and optical characteristics (Tc=25 oC) Parameter Symbol Min. Typ. Peak wavelength 775 785 Threshold current Operating current Operating voltage Differential efficiency Ith 25 35 Iop 90 115 Vop 1.5 2 0.8 1.1 Parallel divergence angle 89 Perpendicular dive [ ... ]

ADL-78901SX PDF Datasheet Download