General Description
1-8 C156-E228-02EN
(3) Actuator section
The actuator section consists of a focus actuator and a tracking actuator. The
former focuses a laser beam on the surface of an optical disk while the latter
moves the beam spot along the radius, on the surface of an optical disk (seek
operation).
The actuator section is directly driven by a linear voice coil motor. The tracking
actuator is based on the pulse-width modulation (PWM) system and realizes low
power consumption and high-speed access.
(4) Separate optical sections
The optical head section has a split structure in which the fixed optics section is
separated from the moving optics section to minimize seek time and positioning
error. This reduces the weight of the moving parts.
The fixed optics section consists of the laser diodes, collimator lens, separation
prism, condensing lens, and the optical detector.
A laser diode for recording and playback transmits one laser beam to the actuator
section.
(5) Panel
The central part of the panel is hollowed out to provide enough space to enable
the cartridge to be inserted by pushing it with a finger, thereby facilitating
insertion.
The panel is also simply designed using an eject button that also serves as LED
light emitting part.
1.2.4 Control circuit section
Figure 1.4 is a block diagram of the control circuit section and the peripheral
sections.