公开(公告)号：JPH0696255A

公开(公告)日：1994-04-08

申请号：JP13063293

申请日：1993-06-01

Applicant: SYMBOL TECHNOLOGIES INC

Inventor： POORU DOBUORUKISU ,  RARUFU TOOMASU ,  DEIBUITSUDO GOOREN ,  ROBAATO FURAA ,  RENAADO EICHI GOORUDONAA

IPC: G06K7/015 ,  G06F3/033 ,  G06K7/10

Abstract: PURPOSE: To make an optical reader convenient to be used for read of information encoded with wide-range densities to improve the efficiency by making the diameter of diffused light at the point, where diffused light is brought into contact with optical encoded information, different between two different distances. CONSTITUTION: When a spacer 21 is attached relatively far ahead of the front end part of a housing 11 and the front end part of the spacer 21 is brought into contact with a surface S, the distance between a focus P and the surface S is relatively long, and the spot of light is large. This case is suitable for read of information encoded with a low density like a bar code printed by a dot matrix. Meanwhile, when the spacer 21 is shortened in the opposite direction on the housing and the front end part or the spacer 21 is brought into contact with the surface S, the distance between the focus P and the surface S is relatively short, and the spot of light is small. This case is suitable for read of information encoded with a high density like a small-sized bar code.

公开(公告)号：JPH07192078A

公开(公告)日：1995-07-28

申请号：JP28195094

申请日：1994-11-16

Applicant: SYMBOL TECHNOLOGIES INC

Inventor： RAJI BURITSUJIRARU ,  DEIBUITSUDO GOOREN

IPC: G06K7/00 ,  G06K7/10

Abstract: PURPOSE: To provide a digitizer for a bar code reader for detecting the edge of a bar code symbol, and measuring the strength of each detected edge by providing a sensor means, means which outputs a timing signal, and decoder means. CONSTITUTION: A digitizer circuit 30 receives an analog signal, and transmits a timing signal 32 and an edge direction signal 34 for each edge detected from this signal. This timing signal 32 and the edge direction signal 34 are allowed to pass through a decoder which operates the processing of a multiple threshold value in single scanning using a software routine. The software routine judges the direction of the edge by the signal 34, and judges the timing of the edge by the signal 32. The software routine judges the relative strength of the continuous edges by using the relative width of each timing pulse. In this case, a decoder algorithm is made many different threshold values in single scanning.