Optical path design for scanning assembly in compact bar code readers
AssigneeSymbol Technologies, Inc.
InventorPaul Dvorkis
Life of this patent
Estimating the term…
Abstract
A compact retro-reflective module for use in electro-optical bar code readers includes components arranged to fold outgoing and incoming light along crossed optical paths. The module is convertible between generating one-dimensional and two-dimensional scan patterns to read bar code symbols.
Claims18
In an electro-optical reader for directing a light beam to, and for detecting light reflected from, a bar code symbol to be read, a retro-reflective scan module, comprising:
- a) a generally planar, rectangular support;
- b) a light source supported by the support, for generating and directing the light beam along a first optical path;
- c) an optical assembly mounted on the support, and including an optical element having a light-collection portion for collecting and re-directing the light reflected from the symbol along a second optical path, and a light-passage portion for allowing the light beam from the light source to pass along the first optical path through the light-collection portion;
- d) a scan assembly including a generally planar, reciprocally oscillatable scan mirror mounted in the first optical path for oscillating movement on the support to reflect the light beam passing through the light-passage portion to the symbol along a third optical path which crosses the second optical path, and also for simultaneously directly receiving the light reflected from the symbol and for directing the received reflected light along a fourth optical path to the light-collection portion;
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- e) a sensor supported by the support and lying in the second optical path, for detecting the collected reflected light re-directed by the light-collection portion and for generating an electrical signal corresponding to the symbol.
In an electro-optical reader for directing a light beam to, and for detecting light reflected from, a bar code symbol to be read, a retro-reflective scan module, comprising:
- a) a generally planar, rectangular support;
- b) a light source supported by the support, for generating and directing the light beam along a first optical path;
- c) a selectively activatable first scan assembly including a generally planar, reciprocally oscillatable first scan mirror mounted in the first optical path for oscillating movement on the support to reflect the light beam from the light source along a second optical path;
- d) an optical assembly mounted on the support, and including an optical element having a light-collection portion for collecting and re-directing the light reflected from the symbol, and a light-passage portion for allowing the light beam along the second optical path to pass through the light-collection portion;
- e) a second scan assembly including a generally planar, reciprocally oscillatable second scan mirror mounted in the second optical path for oscillating movement on the support to reflect the light beam received from the light-passage portion to be directed to the symbol, and also for simultaneously directly receiving the light reflected from the symbol and for directing the received reflected light to the light-collection portion;
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- f) a sensor supported by the support, for detecting the collected reflected light re-directed by the light-collection portion and for generating an electrical signal corresponding to the symbol.
Dependencies are inferred from the claim text.