LASER CONTROL IN SCANNERS

• US 20200137257A1
• Filed: 07/20/2017
• Published: 04/30/2020
• Est. Priority Date: 07/20/2017
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Meyer, Bill, Lopez, Matthew G.
• Granted Patent: US 10,904,404 B2
• Time in Patent Office: Days
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: H03M 1/24 using relatively movable reader and disc or strip
• CPC Class Codes: H03M 1/282 of the pattern-shifting type, e.g. pseudo-random chain code
• CPC Class Codes: H04N 1/024 Details of scanning heads ; Means for illuminating the original
• CPC Class Codes: H04N 1/0282 Using a single or a few point light sources, e.g. a laser diode
• CPC Class Codes: H04N 1/053 in main scanning direction, e.g. synchronisation of line start or picture elements in a line

Abstract

An example device including a laser source for generating a laser pulse, a scanner for mounting the laser source, and a motion detector for detecting a motion of the scanner when the laser pulse scans an object. The motion detector includes an optical sensor for generating an optical signal based on the motion of the scanner, and a controller. The controller determines a movement of the scanner and disables the laser source when the scanner ceases to move.

Claims

1. A device comprising:

a laser source to generate a laser pulse;

a scanner connected to the laser source;

a motion detector to detect a motion of the scanner when the laser pulse scans an object, wherein the motion detector comprises an optical sensor to generate a first optical signal and receive a second optical signal from an encoder based on the motion of the scanner; and

a controller communicatively coupled to the motion detector to disable the laser source when the scanner ceases to move.

2. The device of claim 1, wherein the optical sensor is to:

generate an electrical pulse series when the scanner moves; and

cease generating the electrical pulse series when the scanner ceases to move,

wherein the motion detector comprises a low pass filter to filter the electrical pulse series, and

wherein an output of the low pass filter is at a first level when the scanner ceases to move, and at a second level when the scanner moves.

3. The device of claim 2, wherein the controller comprises a comparator to compare the output of the low pass filter with a threshold level.

4. The device of claim 3, wherein the controller is to disable the laser source when the output of the low pass filter is below the threshold level.

5. The device of claim 3, wherein the controller is to enable the laser source when the output of the low pass filter is above the threshold level.

6. The device of claim 1, wherein the scanner is to scan the object in three dimensions using the laser pulse.

7. A device comprising:

a laser source to generate a laser pulse, wherein the laser source is mounted on a scanning device;

an optical sensor to;

determine whether the scanning device is moving; and

generate a first output comprising an electrical pulse series when the scanning device is moving;

a low pass filter to filter the first output from the optical sensor; and

a first controller to enable or disable the laser source using a second output from the low pass filter.

8. The device of claim 7, comprising a comparator to:

compare the second output from the low pass filter with a threshold level;

generate a first signal when the output from the low pass filter is lower than the threshold level; and

generate a second signal when the output from the low pass filter is greater than the threshold level.

9. The device of claim 8, wherein the first controller is set to:

disable the laser source when the comparator generates the first signal; and

enable the laser source when the comparator generates the second signal.

10. The device of claim 8, comprising a chamber to receive an object to be scanned, wherein the laser source is to scan the object in three dimensions when the laser source is moving.

11. The device of claim 8, comprising:

an electric motor to move the scanning device and the laser source; and

a second controller to control the movement of the scanning device and the laser source,

wherein the first controller and the second controller are communicatively coupled together.

12. A non-transitory computer readable medium comprising instructions that when executed cause a controller of an electronic device to:

control a laser source to generate a laser pulse for scanning an object;

control an optical sensor to generate a first optical signal transmitted to a scanner;

filter a series of electrical pulses generated by the optical sensor in response to receiving a second optical signal from the scanner;

compare a result of the filtering with a predetermined threshold level;

determine a state of movement of the scanner when the result of the filtering is different than the predetermined threshold; and

control an operation of the laser source based on a detected state of movement of the scanner.

13. The non-transitory computer readable medium of claim 12, wherein the series of electrical pulses comprises a fifty percent duty cycle square wave signal.

14. The non-transitory computer readable medium of claim 13, wherein the scanner is to scan the object in three dimensions.

15. The non-transitory computer readable medium of claim 12, wherein control of the operation of the laser source based on a detected state of movement of the scanner comprises instructions that when executed cause the controller of the electronic device to:

disable the laser source when non-movement of the scanner is determined; and

enable the laser source when movement of the object is determined.