Welch Allyn SCANTEAM 2380 WAND Specifications download pdf (Page 16)

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Operational Description

2.3 Scanner Identification Label

The scanner identification label is located on the scanner’s cable. The

identification corresponds to the configuration work sheet description.

(Welch Allyn p/n 16206714)

2.4 Operating Theory

The reading ability of the wand scanner is based on the detection of

reflected illumination from the bars and spaces which form a bar code

symbol.

During a typical scanning operation, the tip of the scanner is moved across

the bar code symbol. Illumination from the LED is focused on the bar

code symbol. This is absorbed by the dark colored bars and reflected by

the lighter background.

The reflected portion re–enters the scanner through the lens where it is

detected by the read sensor photodiode. The photodiode converts this into

a series of analog pulses which are proportional in width to the bars and

spaces in the symbol. These pulses are then digitized and sent to the

microprocessor where they are decoded into the characters represented by

the bar code symbol.

2.5 Factors Affecting Scanning Performance

The following factors influence reading performance and should be

considered when selecting a contact scanner for a particular bar code

application.

2.5.1 Scanner Illumination Source

Wand type scanners are equipped with a visible red (660nm) source.

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Welch Allyn SCANTEAM 2380 WAND Specifications Page 16