JP2004235437A - Laser sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser sensor which can avoid a large size or a cost increase of a device and simultaneously can adjust an irradiation position of laser beams safely and easily. <P>SOLUTION: When a detection operation of a leg pin P of an IC 19 is executed, a change-over switch 15 is set to a detection mode side, and a visible light laser L in which a light intensity is class 2 or above in JIS STD C6802 is emitted from a laser light source 11. On the other hand, when a laser spot S in the leg pin P of the visible light laser L is adjusted, the change-over switch 15 is set to the side of a position adjusting mode, whereby the visible light laser L in which the light intensity is class 1 in JIS STD C6802 is emitted from the laser light source 11. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a laser sensor, and more particularly, to position adjustment of an irradiation point of a laser beam.
[0002]
[Prior art]
Conventionally, as this type of laser sensor, for example, there is a laser sensor that detects the presence or absence of a foot pin in an IC chip manufacturing process. In this method, a laser light emitting unit and a light receiving unit are provided side by side, and a visible light laser is emitted from the laser light emitting unit toward a foot pin of an IC chip placed on a predetermined inspection table, and reflected from the foot pin. It is arranged so that light enters the light receiving unit. Since the amount of light received by the light receiving unit differs depending on whether or not there is a foot pin, the presence or absence of a foot pin can be detected based on this change in the amount of received light.
[0003]
Here, in order to detect the foot pin, it is necessary to adjust the irradiation position of the visible light laser from the laser generating unit on the inspection table. That is, when a normal IC chip (an IC chip having foot pins according to specifications) is placed on the inspection table, the visible light laser from the laser generator is applied to the foot pins of the normal IC chip. A laser sensor must be located. One of the methods is to make the laser sensor execute a light emitting / receiving operation at the time of detecting a foot pin so that a spot of a visible light laser from a laser generating unit is formed on a foot pin of a normal IC chip on an inspection table. It is conceivable that the operator visually adjusts it so that it is adjusted. In particular, in the case of a laser sensor that detects a minute object such as a foot pin of an IC chip, the spot of the visible light laser is also small due to the detection accuracy, so that the irradiation position is adjusted using a magnifying glass (loupe). In some cases, it must be done.
[0004]
Incidentally, in the laser sensor, the light intensity of the laser beam from the laser generator is generally set to class 2 or more of JIS standard C6802 in order to obtain a predetermined detection accuracy. Therefore, as described above, the adjustment of the irradiation position based on the visible light laser having the light intensity of class 2 or more similar to that at the time of detecting the foot pin should be avoided as much as possible. In particular, when a magnifying glass is used, the visible light laser may be focused by the magnifying glass and the light intensity may be further increased.
[0005]
Therefore, for example, there is a type in which a position confirmation plate having a plurality of light receiving elements arranged is opposed to the laser sensor, and the irradiation position of the visible light laser is monitored based on the amount of light received by each of the plurality of light receiving elements. With such a configuration, it is possible to adjust the irradiation position of the visible light laser without looking at it by the operator.
[0006]
[Patent Document 1]
JP 2001-334376 A
[Problems to be solved by the invention]
However, in the above-described conventional device that monitors the irradiation position of the visible light laser based on the amount of light received by the light receiving element, a position confirmation plate, a monitor, and the like are required for that purpose, resulting in an increase in size, complexity, and cost of the device. There was a problem.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a laser sensor capable of safely and easily adjusting a laser beam irradiation position while avoiding an increase in the size and cost of an apparatus. is there.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a laser sensor according to the first aspect of the present invention includes a laser generating unit that emits a visible light laser toward a predetermined detection region, and a light receiving unit that can receive the visible light laser from the detection region. A laser sensor that performs a predetermined detection operation based on the amount of light received by the light receiving unit that changes according to an object in the detection area, and includes a detection mode for performing the detection operation, and a laser generation unit. Mode switching means capable of switching between a position adjustment mode for adjusting the irradiation position of the visible light laser in the detection region, and a light intensity of JIS C6802 when the mode switching means is set to the detection mode side. When the mode switching means is set to the position adjustment mode side while the visible light laser of class 2 or more of the laser is emitted from the laser generating means, the light intensity is adjusted to the JIS standard. Visible light laser of Class 1 C6802 where the control means for controlling the output of the laser generating means so as to emit from the laser generating means is provided with the features.
“Class 1 of JIS standard C6802” is intrinsically safe or a light intensity that is safe by technical design. “Class 2 of JIS standard C6802” is a laser that emits visible radiation in a wavelength range of 400 nm to 700 nm, and has a light intensity that can protect eyes by an aversive reaction including a normal blinking reflection action. "Class 3 of JIS C6802" is a laser that is safe for observation with the naked eye. For a laser that emits in the wavelength range of 400 nm to 700 nm, protection is provided by an aversive reaction including the reflective action of blinking. You.
[0010]
According to a second aspect of the present invention, in the laser sensor according to the first aspect, the laser generating means forms a laser spot on the detection area by focusing a laser light source for outputting a visible light laser and the incident visible light laser. And a focusing optical system for emitting visible light laser output from the laser light source through the focusing optical system.
[0011]
Function and effect of the present invention
<Invention of claim 1>
According to this configuration, when a normal detection operation is to be performed, the mode switching unit is set to the detection mode. As a result, a visible light laser having a light intensity of class 2 or more according to JIS C6802 is emitted from the laser generating means, and the above detection operation is executed. On the other hand, for example, at the stage of installing the laser sensor, if it is desired to adjust the irradiation position of the visible light laser from the laser generation means in a predetermined detection area, the mode switching means is set to the position adjustment mode. As a result, a visible light laser having a light intensity of class 1 of JIS standard C6802 is emitted from the laser generating means. Then, position adjustment is performed based on the irradiation position of the visible light laser having the light intensity of class 1.
[0012]
As described above, since the light intensity of the visible light laser from the laser generating means during the detection operation is equal to or higher than class 2, it is possible to obtain high detection accuracy. On the other hand, since the light intensity of the visible light laser from the laser generating means at the time of position adjustment is class 1, the irradiation position of the laser light can be directly viewed or a magnifying glass (loupe) or the like can be used without adding a configuration such as a position detecting element or a monitor. The position adjustment can be performed safely and easily while using and confirming.
[0013]
<Invention of Claim 2>
According to this configuration, the laser generation unit includes a laser light source that outputs a visible light laser, and a focusing optical system, and emits the visible light laser output from the laser light source through the focusing optical system. It is configured. Such a laser sensor has an extremely small spot of laser light and is suitable for detecting a minute object. However, in order to confirm the position of the minute spot, it is necessary to use a magnifier having a higher magnification. However, also in this configuration, since the light intensity of the laser beam from the laser generating means is at least class 2 at the time of the detecting operation and class 1 at the time of the position adjustment, high detection accuracy is obtained, and a direct view or a magnifying glass (loupe) is used. The position can be adjusted safely and easily while confirming the position.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 3 by taking a laser sensor 10 used for detecting the presence or absence of a foot pin P in a manufacturing process of an IC chip 19 as an example. I do.
[0015]
The laser sensor 10 according to the present embodiment includes a laser light source 11 (for example, a laser diode) and a light receiving unit 12, and a visible light laser L emitted from the laser light source 11 is mounted on an IC chip 19 disposed on a predetermined inspection table. The light is irradiated toward the foot pin P, and the light is reflected from the foot pin P so as to enter the light receiving unit 12. Then, the foot pin P of the IC chip 19 is detected based on a change in the amount of light received by the light receiving unit 12 when the foot pin P is present on the IC chip 19 on the inspection table.
[0016]
More specifically, as shown in FIG. 1, the laser sensor 10 includes a box-shaped case 13 having a cut-out corner, and a laser light source 11 for emitting a visible light laser L, 12 are arranged side by side. Further, on the upper surface of the case 13, a slide type changeover switch 15 (corresponding to "mode switching means" of the present invention) is provided, which can be switched between a detection mode and a position adjustment mode, as described later. I have. A cable 18 that bundles, for example, a power supply line is led out of the cutout portion 17 of the case 13, and the cable 18 is connected to, for example, an external device (not shown) (for example, a power supply circuit or a control device) to connect to a power supply. It is supplied.
[0017]
Next, the configuration inside the case 13 will be described. As shown in FIG. 2, a case 13 includes first and second drive circuits 21 and 22 selectively connected to the laser emission unit by a switch element 23, a CPU 20, and a changeover switch 15. Are provided. The switch element 23 performs a switching operation according to a control signal from the CPU 20 as described later. When the first drive circuit 21 receives the control signal from the CPU 20, the first drive circuit 21 outputs a drive signal of a level such that the visible light laser L having a light intensity of, for example, class 2 of JIS C6802 is emitted from the laser emitting unit. . Note that Class 2 of JIS C6802 refers to light intensity which is not inherently safe but can be protected against eyes by an aversive reaction including a normal blink reflection action. On the other hand, when receiving the control signal from the CPU 20, the second drive circuit 22 outputs a drive signal of a level such that the visible light laser L having a light intensity of, for example, class 1 of JIS C6802 is emitted from the laser emitting unit. . Therefore, in the present embodiment, the switch element 23, the CPU 20, and the first and second drive circuits 21 and 22 constitute "control means" of the present invention. Class 1 of JIS C6802 refers to light intensity that is inherently safe or safe due to technical design.
[0018]
Furthermore, in the present embodiment, a focusing lens 16A (corresponding to the “focusing optical system” of the present invention) that focuses the visible light laser L output from the laser light source 11 is disposed on the front surface of the laser light source 11. Thereby, a minute laser spot S can be formed on the inspection table. A focusing lens 16B is also provided on the front surface of the light receiving unit 12, so that more light reflected from the foot pin P enters the light receiving unit 12.
[0019]
Next, the control contents of the CPU 20 will be described with reference to the flowchart shown in FIG. When the power is turned on, the CPU 20 detects in step S1 which mode the changeover switch 15 is set to, and when the changeover switch 15 is set to the detection mode ("Y" in step S1). Then, the switch element 23 is driven so that the first drive circuit 21 is connected to the laser light source 11. Then, in step S2, a control signal is given to the first and second drive circuits. Thus, the laser light source 11 operates to emit the visible light laser L having the light intensity of class 2. Further, in synchronization therewith, the light receiving signal level at the light receiving section 12 is read (step S4), the light receiving signal level is compared with a predetermined threshold value, and a detection signal corresponding to the comparison result is sent to the cable 18. Output (Step S5).
[0020]
On the other hand, when the changeover switch 15 is set to the position adjustment mode instead of the detection mode (“N” in step S1 and “Y” in step S6), the second drive circuit 22 is connected to the laser light source 11. Switch element 23 is driven. Then, in step S8, a control signal is given to the first and second drive circuits. Thereby, the laser light source 11 operates to emit the visible light laser L having the light intensity of class 1.
[0021]
Now, the operation and effect of the laser sensor 10 according to the present embodiment will be described.
<When adjusting the position of the laser spot>
For example, in order to adjust the position of the laser spot S of the visible light laser L when setting the laser sensor 10, first, a normal IC chip 19 (an IC chip having foot pins P as specified) is placed on an inspection table. Then, the laser sensor 10 is disposed above the laser sensor 10. When the switch 15 is set to the position adjustment mode and the power is turned on, the laser light source 11 emits a visible light laser L having a light intensity of class 1 and forms a small laser spot S on the inspection table. Therefore, the position of the laser spot S of the visible light laser L can be adjusted by finely adjusting the arrangement position of the laser sensor 10 so that the laser spot S is located on the foot pin P to be detected. At this time, since the foot pin P to be detected and the laser spot S of the visible light laser L are very small, it may be necessary to perform position adjustment by enlarging and viewing using a magnifying glass (loupe).
[0022]
<When detecting a foot pin>
When the position adjustment of the laser spot S is completed, the IC chip 19 to be inspected is placed on the inspection table, and the switch 15 is switched to the detection mode. Then, the visible light laser L having the light intensity of class 2 is emitted from the laser light source 11, and the above-described light emitting / receiving operation is executed. As a result, the magnitude relationship between the light receiving signal level in the light receiving unit 12 and the threshold value is inverted depending on the presence or absence of the predetermined foot pin P to be inspected in the IC chip 19, and the detection signal is externally transmitted via the cable 18 accordingly. Give to equipment.
[0023]
As described above, according to the configuration of the present embodiment, since the light intensity of the visible light laser L from the laser light source 11 during the detection operation is equal to or higher than class 2, it is possible to obtain high detection accuracy. On the other hand, since the light intensity of the visible light laser L from the laser light source 11 at the time of position adjustment is class 1, not only the case where the position of the laser spot S of the visible light laser L is directly viewed but also the case where a magnifying glass is used. However, position adjustment can be performed safely. Therefore, position adjustment can be performed with a relatively easy configuration without adding a configuration such as a position detection element and a monitor.
[0024]
<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and furthermore, besides the following, within the scope not departing from the gist. Can be implemented with various modifications.
(1) In the above-described embodiment, the changeover switch 15 operated by the operator is used as the “mode switching means”. However, for example, a signal transmitted by a predetermined input operation or the like on the external device side is received, and the signal is received. A configuration in which a mode switching operation is performed in response thereto may be employed.
(2) In the above embodiment, the focusing lens 16A is arranged in front of the laser light source 11, but the visible light laser L emitted from the laser light source 11 is directly sent to the inspection table side without providing the focusing lens 16A. Irradiation may be adopted. However, with the configuration in which the focusing lens 16A is provided as in the present embodiment, it is possible to accurately detect even a minute object such as the foot pin P of the IC chip 19 as described above.
[0025]
(3) In the present invention, the “focusing optical system” in the present invention is a single focusing lens. However, the present invention is not limited to this. The focusing lens is provided with a plurality of lenses, and focuses and emits the incoming visible light laser L. There may be.
(4) In the above embodiment, the light intensity of the visible light laser L in the detection mode is set to class 2 of JIS C6802, but may be set to class 3 or more.
[0026]
(5) In the present embodiment, the so-called reflection type laser sensor 10 that reflects and detects the visible light laser L to the detection area is used. However, the present invention is not limited to this. The same effects as in the first embodiment can be obtained by applying the present invention to a so-called transmissive type in which the devices are arranged so as to sandwich them.
(6) In the above embodiment, the output of the laser light source 11 is controlled by the switch element 23 and the two drive circuits. However, the present invention is not limited to this, and different signals are received according to the set mode. It may be constituted by a variable amplifier circuit or the like that changes the drive signal level given to the laser light source 11 according to the signal.
[0027]
(7) In the above-described embodiment, the laser sensor 10 used for detecting the presence or absence of an object (detecting the foot pin P of the IC) is described. The deformation of the foot pin of the IC chip or the like may be detected based on the amount of light received by the light receiving unit. In addition, for example, a laser sensor that is used to irradiate an inspection target with laser light and detect a distance measurement, a displacement amount measurement, and the like to the inspection target based on an amount of received reflected light may be used.
(8) In the above embodiment, the laser sensor 10 in which the laser light source 11, the light receiving unit 12, the drive circuits 21, 22, the CPU 20, and the like are housed in one case 13 is not limited to this. So-called head separation, in which a sensor head provided with a unit or a sensor head provided with a laser light source, a light receiving unit, and a drive circuit, and a controller provided with other components (such as a CPU) are connected via a cable. Type sensor head.
[Brief description of the drawings]
FIG. 1 is a perspective view of a laser sensor according to an embodiment of the present invention; FIG. 2 is a configuration diagram in a case thereof; FIG. 3 is a flowchart showing processing of a CPU;
10 laser sensor 11 laser light source 12 light receiving section (light receiving means)
15. Changeover switch (mode switching means)
16A: Focusing lens (focusing optical system)
19: IC chip 20: CPU
21 first drive circuit 22 second drive circuit 23 switch element P foot pin L laser light S laser spot

Claims (2)

Laser generating means for emitting a visible light laser toward a predetermined detection area, and light receiving means capable of receiving the visible light laser from the detection area, wherein the light-receiving means changes according to an object in the detection area. A laser sensor that performs a predetermined detection operation based on the amount of light received by the light receiving means,
A detection mode for performing the detection operation, and a mode switching unit that can be switched between a position adjustment mode for adjusting the irradiation position of the visible light laser from the laser generation unit in the detection region,
When the mode switching means is set to the detection mode side, the visible light laser having a light intensity of class 2 or more of JIS standard C6802 is emitted from the laser generation means,
When the mode switching means is set to the position adjustment mode side, control for controlling the output of the laser generating means so that the visible light laser of the light intensity of class 1 of JIS C6802 is emitted from the laser generating means. A laser sensor comprising: The laser generating means includes a laser light source that outputs a visible light laser, and a focusing optical system that focuses the incident visible light laser to form a laser spot in the detection region, and is output from the laser light source. The laser sensor according to claim 1, wherein the laser sensor is configured to emit a visible light laser through the focusing optical system.

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