ID-01 Laser Scanner User’s Manual
A-19
Appendices
Raster Picket Fence Calculation
For raster picket fence scanning, the number of decodes
(ND) that can be applied to a given symbol can be calcu-
lated once the sweep rate (SR) is known.
Sweep Rate
(SR)
Sweep rate is the number of raster sweeps (up or down)
that occur per second and can be set in
di-soric ID
.
Since the sweep rate cannot exceed 30 you first need to
ensure that your application can achieve this by solving
for sweep rate. The sweep rate should generally be set
as low as possible in order to maximize the number of
scans on a given symbol.
The formula for determining
Sweep Rate
(SR) is as follows:
1
SR
= Sweep Rate, the number of passes, up or down, that are described by the arc of the raster
mirror.
SS
= Scan Speed, the distance per second that a symbol moves through the scan.
SW
= Scan Width, the width across the scan beam, at a given distance from the scanner, in which a
symbol can be read (picket fence formula only).
SL
= Symbol Length, the length of the longest printed symbol to be read plus the length of the quiet
zones (picket fence formula only).
Example:
Important
: The maximum sweep rate that your can set the scanner to is 80. If your solu-
tion is greater than 80, you must change another parameter such as scan speed, etc. and
recalculate.
Since SR can only be entered into the software as whole numbers, round off fractions of
SR to the next higher number, for example enter 0.4 as 1 and 3.5 as 4.
In setting up the scanner, raster height depends on the raster arc and the symbol distance
(range) from the scanner. Both the top offset and bottom offsets can be adjusted indepen-
dently in 255 increments and the resulting arc can vary from 0° to 30°.
1. The number 2 in the SR formula ensures that each symbol receives two full raster sweeps.
Direction of symbol travel
Raster pattern
Raster
Picket Fence
SR
2 SS
SW SL
–
---------------------------
=
SW
5
=
SS
2 inches per second
=
SL
1
=
SR
2 2
5 1
–
----------------
1
=
=
Summary of Contents for ID-01
Page 1: ...ID 01 Laser Scanner User s Manual ID 01 User s Manual ...
Page 12: ...xii ID 01 Laser Scanner User s Manual ...
Page 24: ...1 12 ID 01 Laser Scanner User s Manual Configure the Scanner ...
Page 58: ...3 20 ID 01 Laser Scanner User s Manual Intercharacter Delay ...
Page 78: ...4 20 ID 01 Laser Scanner User s Manual Scanner Setup ...
Page 82: ...4 24 ID 01 Laser Scanner User s Manual Laser Setup ...
Page 110: ...5 28 ID 01 Laser Scanner User s Manual Symbol Ratio Mode ...
Page 156: ...8 10 ID 01 Laser Scanner User s Manual Service Message ...
Page 164: ...9 8 ID 01 Laser Scanner User s Manual Auto Frame ...
Page 170: ...10 6 ID 01 Laser Scanner User s Manual Terminal Window Menus ...
Page 190: ...11 20 ID 01 Laser Scanner User s Manual Scanner Status Requests ...
Page 222: ...A 32 ID 01 Laser Scanner User s Manual Glossary of Terms ...