Omron ZG -, Руководство пользователя

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Basic Knowledge for Operation
156
ZG User’s Manual
Basic Knowledge for Operation
CCD Mode
Expression of Images on the ZG Series
The ZG series uses a CCD (Charge Coupled Device) as the receiver element. CCDs are
widely used in digital cameras and image scanners, for example. These semiconductor
devices are highly accurate and highly reliable, and can achieve a high resolution as a sensor.
Pixel array and coordinate axes
Profiles acquired by the ZG series are expressed in the form of an array comprising small
squares called “pixels” arranged in the horizontal and vertical directions. In the standard
mode (631 x 100 pixels), acquired images are expressed by 631 pixels arranged in the
horizontal direction and 100 pixels arranged in the vertical direction. With this array, the
horizontal and vertical directions are called the “coordinate axes”, with the vertical (Z-axis)
indicating the measurement result in the height direction, and the horizontal axis (X-axis)
indicating the measurement result in the width direction.
Number of pixels and resolution
To express the clarity on a digital camera or image scanner, the term “resolution” is used.
The same approach is used on the ZG series, too. A “high resolution” expresses a sharp
image, while a “low resolution” expresses a grainy image. Resolution is determined by the
number of pixels per unit area. Though a sharper or higher resolution image is obtained,
the more pixels there are per unit area, processing takes that much longer proportionate
to the amount of information for that image.
Z-axis
X-axis
Width direction
Height
direction
Pixel
Standard images look flat.
Surfaces, in fact, are slightly uneven.