JP2682237B2 - Deterioration detection device for laser light output device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deterioration detecting device for detecting the degree of deterioration of a laser light output device such as a semiconductor laser.

[0002]

2. Description of the Related Art In general, a measuring instrument to which a semiconductor laser is applied can perform extremely highly accurate measurement, so that the measuring instrument is now used in various industrial fields.

[0003]

However, a device that outputs laser light, such as a semiconductor laser, has a very long life because it is very difficult to determine the degree of deterioration, and the device cannot be installed. Unpredictable obstacles may occur depending on the location. For example, when a measuring device to which the semiconductor laser is applied is used in a production line of an automobile, if the semiconductor laser reaches the end of its life, the decrease in the output intensity will hinder the measurement. Further, since it is difficult to schedule maintenance for replacement or adjustment of the semiconductor laser, there is a problem that the line may be forced to be stopped during the replacement or adjustment. The present invention has been made in view of the above conventional problems, and paying attention to the fact that the output intensity of laser light decreases with the aging of the laser light output means. The degree of deterioration of the output device can be easily grasped, and the scanning speed of the laser beam to the measured object is automatically corrected according to the degree of deterioration so that accurate measurement can be performed regardless of the deterioration. An object of the present invention is to provide a deterioration detection device for a laser light output device that can be performed.

[0004]

The present invention for achieving the above object provides a laser light output means for outputting a laser light, a light receiving means for receiving the laser light, and a laser light from the laser light output means. A reflection means for reflecting the laser light toward the light receiving means, a storage means for storing aging information of the laser light output intensity in the laser light output means, and the laser light received by the light receiving means via the reflecting means. It is characterized in that it has a detection means for detecting the degree of deterioration of the laser light output means from the output intensity of the laser light from the output means and the secular change information stored in the storage means.

[0005]

In the present invention thus constructed, the laser light from the laser light output means reflected by the reflecting means is received by the light receiving means, so that the output intensity of the laser light in the present laser light output means is received. Is measured
The measured output intensity is compared with the secular change information stored in the storage means to detect the degree of deterioration of the laser light output means. The secular change information stored in the storage means is information from the initial use to the end of life of the output intensity and time of the laser beam input to the light receiving means via the reflecting means. Therefore, the current degree of deterioration of the laser light output means can be easily grasped, and the replacement and adjustment of the laser light output means can be predicted and maintained.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram of a deterioration detection device of a laser light output device according to the present invention, and FIG. 2 is a schematic configuration diagram of a portion for measuring the intensity of laser light in the device shown in FIG. The laser diode 10 functions as a laser light output means, and from this, laser light is output toward an object to be measured, which is an object to be subjected to dimension or shape measurement. The laser diode 10 is driven by a laser diode drive unit 11. The PSD sensor 12 functions as a light receiving unit, and receives the laser light from the laser diode 10 reflected by the shutter 13. The shutter 13 is driven for a predetermined time by the control unit 14, and the laser light from the laser diode 10 is PS only while the shutter 13 is driven.
It will be reflected toward the D sensor 12. During this period, the intensity of the laser light received by the PSD sensor 12, in other words, the amount of received light is input to the control unit 12 as information. Further, the control unit 14 is adapted to count the cumulative use time after the laser diode 10 is replaced. In the storage unit 15, the relationship between the use time and the laser light output of the laser diode 10 as shown in FIG. 3 is shown for each mode of collimation (curve A), use (curve B) and life (curve C). Remembered
In addition, the intensity of the laser light of the laser diode 10 from the past to the present, which is collected at every deterioration detection, and the accumulated use time are also sequentially stored. The control unit 14 compares the information of the intensity of the laser light input to the PSD sensor 12 and the usage time of the PSD sensor 12 with the above-mentioned information stored in the storage unit 15, and the comparison result is obtained. The state of the laser diode 10 will be grasped based on this. The notification unit 16 notifies the comparison result by the control unit 14, and normally causes the display plate to display the result. The scan time correction unit 17 scans the laser diode 10 toward the object to be measured, corrects the scanning speed thereof, and outputs the corrected scanning speed to the robot drive control unit 18. The robot drive controller 18 controls the operation of the robot for scanning the laser diode 10.

Laser diode 10, PSD described above
The sensor 12 and the shutter 13 are housed in a casing 20 as shown in FIG. This casing 20
Is attached to an arm portion of a robot (not shown), and the laser beam is scanned on the object to be measured by scanning the arm portion. Laser diode 10
Emits a laser beam toward the shutter 13. When the measurement is being performed, the shutter 13 is not driven, and the laser light output from the laser diode 10 passes through the shutter 13 and is applied to the object to be measured. Incidentally, the shutter 13 is a liquid crystal shutter which has been widely used recently. When the shutter 13 is driven, the laser light from the laser diode 10 does not pass through the shutter 13 and is reflected by the shutter 13, and the reflected light is provided at the back of the laser diode 10.
The light is received by the D sensor 12. In addition, this PS
As described above, the amount of light received by the D sensor 12 is input to the control unit 14, and the state of the laser diode 10 is determined based on the information stored in the storage unit 15.

The deterioration detecting device of the laser light output device constructed as described above operates as shown in the operation flowchart of FIG. First, when a command to detect deterioration of the laser diode 10 is input from the outside to the control unit 14, the control unit 14 drives the shutter 13 and closes the shutter 13 so that the laser light is incident on the PSD sensor 12. (S1). Next, the control unit 14
Outputs a signal for driving the laser diode 10 to the laser diode drive section 11, and the laser diode drive section 11 receives the command and drives the laser diode 10 to output a laser beam (S2). Next, the control unit 14 replaces the intensity of the laser light received by the PSD sensor 12 with the light amount and inputs it, and the light amount and the cumulative use time of the laser diode 10 counted by the control device 14 are input to the laser diode 1
The information of 0 is stored in the storage unit 15 (S3, S4).
Then, every time the deterioration is detected in the storage unit 15, it is judged whether or not this information stored up to the present time and the information as shown in FIG. Then, it is determined next whether the pattern of the information is A, B, or C. Whether or not the information is compared is determined uniformly based on how long the integrated use time of the laser diode 10 is, or how much light is received. The judgment may be made in combination. Specifically, the information is compared because the accumulated use time is equal to or longer than T time, in other words, whether the deterioration of the laser diode 10 is detected or whether the deterioration is detected because the light quantity is Q lumens or less. Alternatively, it may be determined by performing deterioration detection or the like because the accumulated use time is equal to or longer than T time and the light amount is equal to or less than Q lumen (S5).

Whether or not to compare the information is determined according to the above-described criteria. If it is determined that the information is to be compared, the information stored in step S4 is 3 corresponds to the A pattern showing the defective pattern at the time of collimation, the B pattern showing the defective pattern at the time of use, or the C pattern showing the life pattern. It is determined whether or not it is equivalent (S6 to S
8), if it does not correspond to any of the patterns, the control unit 1
4 causes the notification unit 16 to display that the laser diode 10 is normal (S9). On the other hand, if any of the patterns is satisfied in this determination, the control unit 14
The deterioration degree is calculated by comparing the information of the laser diode 10 in the corresponding pattern stored in the storage unit 15 with the information stored in the step of S4, and the scan time correction unit 17 is operated according to the deterioration degree. Command to set the scan time of the laser beam. Scan time correction unit 17 that received this command
Outputs to the robot drive controller 18 a command to slow down the scanning speed when the laser beam is scanned on the object to be measured. As a result, for example, if the output intensity of the laser light is reduced to about 90% at the time of replacement, the scanning speed of the laser light scanned by the robot on the object to be measured is reduced by about 10%. For this,
Since the measurement is always performed in the optimum state, the reliability and stability of the measurement are improved (S10, S1).
1). Further, in the comparison in the step S10, when the intensity of the laser light is so low that it is determined that it has reached the end of its life, the control unit 14 causes the notification unit 16 to display that the laser diode 10 is at the end of its life (S1).
2).

The above processing is performed by the laser diode 1.
It is performed every fixed use time of 0. In addition, the shutter 13 performed in steps S1 and S2
Driving of the laser diode 10 and driving of the laser diode 10 are started almost at the same time and ended almost at the same time. Therefore, PSD
The sensor 12 is irradiated with the laser light for a set period of time, and the controller 14 detects the deterioration of the laser diode 10 based on the amount of light received during this period. It is also possible to calculate the remaining life of the laser diode 10 in use by further advancing this deterioration detection. If this life expectancy can be calculated, perfect preventive maintenance can be easily performed.

[0011]

As described above, according to the present invention, the deterioration state of the laser light output means can be easily determined, so that perfect preventive maintenance can be performed and the replacement thereof can be produced. It can be performed without adversely affecting the operation of the line.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a deterioration detection device of a laser light output device according to the present invention.

FIG. 2 is a schematic configuration diagram of a portion for measuring the intensity of laser light in the apparatus shown in FIG.

FIG. 3 is a diagram showing an example of information stored in a storage unit of the apparatus shown in FIG.

FIG. 4 is an operation flowchart of the apparatus shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Laser diode (laser light output means) 11 ... Laser diode drive part 12 ... PSD sensor (light receiving means) 13 ... Shutter (reflection means) 14 ... Control part (detection means) 15 ... Storage part (storage means) 16 ... Notification Part 17 ... Scan time correction part 18 ... Robot drive control part 20 ... Casing

Claims (1)

(57) [Claims] 1. Laser light output means for outputting laser light, light receiving means for receiving the laser light, reflecting means for reflecting the laser light from the laser light output means toward the light receiving means, and the laser. Storage means for storing secular change information of laser light output intensity in the light output means, and output intensity of laser light from the laser light output means received by the light receiving means via the reflecting means and stored in the storage means A deterioration detection device for a laser light output device, comprising: a detection unit that detects the degree of deterioration of the laser light output unit based on the stored aging information.