ALTANA Color-View - Manual (Page 34)

color-view™ Spectrophotometer User’s Guide
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3.1.1
Basic System Operation
The basic
color-view™ Spectrophotometer System is composed of a
Spectrophotometer, Host Computer System, and Printer (see Figure
1-1 in Chapter 1).
3.1.2
Operation of the Spectrophotometer
The basic operation of the spectrophotometer and its components
(such as Polychromator, A/D Converter, Microcomputer, and I/O
interface) is discussed in this section. Sample measurements are
obtained with the Spectrophotometer in the same manner outlined
below.
The Sample is placed over the Aperture on the Sample Port. A
tungsten-halogen lamp is used as the light source to provided
illumination onto the Sample. This type of lamp is used because of
its stability and continuous output over the visible spectrum.
The light beam is projected through a fiberoptic cable and is applied
circumferentially at an angel of 45° onto the specimen plane. A
portion of the reflected light is collected at an angle of 0°,
perpendicular to the material, and transmitted into the
Polychromator. This collected portion is called the diffuse
reflectance factor.
The Polychromator contains an optical grating which reflects the
sample light onto an array of detectors. The Detector Array detects
the refracted light and converts it to analog electrical signals. The
Analog/Digital (A/D) Converter converts the analog signals collected
directly from the array into digital signals for further processing by
the Microprocessor.