EPSON Stylus Scan 2500 Revision A

Operating Principles Scanner Principles 50

2.3 Scanner Principles
This section explains the operating principles of the scanner mechanism. The
scanner mechanism can be divided into the Carriage Unit and Carriage
Operation.

2.3.1 Carriage Unit

The Carriage Unit is mainly composed of the CCD sensor board, inverter
board, lamp (light source), mirror, and lens. (See Figure 2-18 and Fi g ur e 2-19.)

Figure 2-18. Carriage Unit Component

CCD Sensor Board: This board controls the Color CCD line sensor
(independent R,G,B) and drive circuit.When power
is turned on and the LCD display shows "Warm up",
the CCD sensor board is actually performing a
standard white test.
Inverter Board: This board provides voltage to drive the lamp.
Lamp: A white cold fluorescent lamp is used as the light
source.
Mirror and Lens: The light emitted to the document reaches the CCD
sensor after being reflected on some mirrors one after
another. Instead of changing the light source to
create R/G/B light component as many previous
models did, the color CCD itself creates each R/G/B
light component.

Figure 2-19. Mirror, Lens Mechanism