Mobile code reading device and code reading method

Patent metadata

Field	Value
Publication number	US-12373657-B2
Application number	US-202418409028-A
Country	US
Kind code	B2
Filing date	Jan 10, 2024
Priority date	Feb 10, 2023
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

Achieved are both high speed in decoding a simple code and stability of decoding of a difficult code. A code image, generated by high-speed imaging control (first imaging control) for causing an imaging unit to generate the code image while causing an illumination unit to execute one type (N1=1) of illumination mode (a polarized illumination mode) among four types of illumination, is decoded by a core (high-speed decoding). On the other hand, a code image, generated by difficult-to-read imaging control (second imaging control) for causing the imaging unit to generate the code image while causing the illumination unit to execute all the four types (N2=4) of illumination modes among the four types of illumination modes, is decoded by a core (difficult-to-read decoding).

First claim

What is claimed is:

1. A code reading device comprising:
an illumination unit capable of sequentially executing a plurality of types of illumination modes for irradiating a workpiece, provided with a code to be read, with light in mutually different modes in a switching manner;
an imaging unit that receives light emitted from the illumination unit and then reflected by the workpiece to generate a code image; and
a control unit that includes a first core and a second core capable of decoding code images in parallel, causes the imaging unit to generate a code image while causing the illumination unit to execute one illumination mode among the plurality of types of illumination modes, and causes the first core or the second core to execute decoding of the generated code image, wherein
the control unit executes first imaging control for causing the imaging unit to generate a code image while causing the illumination unit to execute N1 types (N1 is an integer of one or more) of illumination modes among the plurality of types of illumination modes, and a second imaging control for causing the imaging unit to generate a code image while causing the illumination unit to execute N2 types (N2 is an integer larger than N1) of illumination modes among the plurality of types of illumination modes,
the first core executes decoding of the code image generated by the first imaging control, and
the second core executes decoding of the code image generated by the second imaging control in parallel with the decoding by the first core.

2. The code reading device according to claim 1 , wherein the N2 types of illumination modes executed in the second imaging control include at least any one of illumination modes in which light is emitted by diffuse illumination, polarized illumination, ring illumination, or low-angle illumination.

3. The code reading device according to claim 2 , wherein the N2 types of illumination modes further include an illumination mode in which light is emitted by non-diffuse illumination, and the illumination mode is also included in the N1 types of illumination modes executed in the first imaging control.

4. The code reading device according to claim 2 , wherein
the control unit further includes a third core capable of decoding a code image in parallel with the first core and the second core, and executes third imaging control for causing the imaging unit to generate a code image while causing the illumination unit to execute N3 types (N3 is an integer larger than N1) of illumination modes among the plurality of types of illumination modes,
the third core executes decoding of the code image generated by the third imaging control,
the N3 types of illumination modes executed in the third imaging control include at least any one of illumination modes in which light is emitted by the diffuse illumination, the polarized illumination, the ring illumination, or the low-angle illumination, and
while the second core executes decoding of a code image generated based on first illumination among the diffuse illumination, the polarized illumination, the ring illumination, and the low-angle illumination, the third core executes decoding of a code image generated based on second illumination, different from the first illumination, among the diffuse illumination, the polarized illumination, the ring illumination, and the low-angle illumination.

5. The code reading device according to claim 1 , wherein
the illumination unit includes diffuse illumination that irradiates the workpiece with diffuse light obtained by diffusing light emitted from a light source by a diffuser, and non-diffuse illumination that irradiates the workpiece with the light emitted from the light source without the diffusion by the diffuser, and
the N2 types of illumination modes executed in the second imaging control include an illumination mode in which light is emitted by the diffuse illumination and an illumination mode in which light is emitted by the non-diffuse illumination.

6. The code reading device according to claim 5 , wherein
light is emitted by the non-diffuse illumination in the N1 types of illumination modes executed in the first imaging control, and
the first core executes decoding of a plurality of code images generated based on the non-diffuse illumination while the second core executes decoding of a code image generated based on the diffuse illumination and decoding of a code image generated based on the non-diffuse illumination.

7. The code reading device according to claim 5 , wherein
the illumination unit is capable of irradiating the workpiece with light from a plurality of irradiation angles different from each other by the diffuse illumination, and is capable of emitting light by each of a plurality of diffuse illumination modes having mutually different combinations of irradiation angles at which light is emitted among the plurality of irradiation angles,
the plurality of types of illumination modes include the plurality of diffuse illumination modes, and
the second core executes decoding of a plurality of code images generated based on the plurality of diffuse illumination modes while the first core executes decoding of a plurality of code images generated based on the non-diffuse illumination.

8. The code reading device according to claim 5 , wherein
the illumination unit is capable of irradiating the workpiece with light from a plurality of irradiation angles different from each other by the diffuse illumination, and is capable of emitting light by each of first diffuse illumination and second diffuse illumination which have mutually different combinations of irradiation angles at which light is emitted from among the plurality of irradiation angles,
the plurality of types of illumination modes include an illumination mode in which light is emitted by the first diffuse illumination and an illumination mode in which light is emitted by the second diffuse illumination,
the control unit further includes a third core capable of decoding a code image in parallel with the first core and the second core and a fourth core capable of decoding a code image in parallel with the first core, the second core, and the third core, and executes third imaging control for causing the imaging unit to generate a code image while causing the illumination unit to execute N3 types (N3 is an integer larger than N1) of illumination modes among the plurality of types of illumination modes and fourth imaging control for causing the imaging unit to generate a code image while causing the illumination unit to execute N4 types (N4 is an integer larger than N1) of illumination modes among the plurality of types of illumination modes,
the third core executes decoding of the code image generated by the third imaging control,
the fourth core executes decoding of the code image generated by the fourth imaging control, and
the second core, the third core, and the fourth core decode code images generated based on mutually different types of illumination among the non-diffuse illumination, the first diffuse illumination, and the second diffuse illumination.

9. The code reading device according to claim 1 , wherein
the imaging unit includes a first camera and a second camera that has higher resolution than the first camera,
each of the first camera and the second camera is capable of receiving light reflected by the workpiece to generate a code image,
in the first imaging control, only the first camera out of the first camera and the second camera is used to generate a code image, and
in the second imaging control, both the first camera and the second camera are used to generate code images by switching a camera to be used to generate a code image between the first

Assignees

• Keyence Co Ltd

Inventors

• Oki Shusuke

Classifications

• G06K7/10722

  Photodetector array or CCD scanning · CPC title

• G06K7/10

  by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation · CPC title

• G06K7/10732 Primary

  Light sources · CPC title