Optical CD or DVD read-write device has a combined optical unit for beam collimation and reflection of a beam component for checking the beam power so that a more compact design is made possible

摘要

Optical CD or DVD read-write device (1) has a laser diode for generation of light beam (10) with an external photo-diode monitor (3) used to check the emitted light power. A single optical unit (20) with twin elements (4, 5) serves both to collimate the read-write component (13) of the light beam (10) and to split-off the component of the light beam (14) used for checking the light power.