Inspection or exposure light irradiation system

Abstract

To provide a light irradiation system having a configuration in which lighting of a light irradiation device is made to be capable of being performed by a host computer via a controller, where unexpected lighting of the light irradiation device at the time of start-up is prevented using a simple configuration even when any of the controller and the host computer is started up first.SOLUTION: A light irradiation system comprises: a light irradiation device 1 for radiating a work-piece with light for inspection or light exposure; and a controller 2 for controlling lighting / lights-out of the light irradiation device 1 on the basis of an external control signal having high / low two values. The controller 2 controls the light irradiation device 1 so as to be in a lights-out state until a high value is detected as a value of the external control signal after start-up in the case that the external control signal is low active; and controls the light irradiation device 1 so as to be in the lights-out state until a low value is detected as the value of the external control signal after start-up in the case that the external control signal is high active.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light irradiation system used for surface inspection, mark reading inspection, or exposure of a workpiece. [Background technology]

[0002] As shown in Patent Document 1, this type of conventional light irradiation system consists of two devices: a light irradiation device that uses an LED as a light source, and a control device that supplies current to the light irradiation device and controls its lighting.

[0003] This control device is provided with an input port for receiving an external control signal, and is configured to control the on / off of the light irradiation device according to the value of an external control signal that takes two values, high or low, input to this input port from, for example, a higher-level host computer used by the user. Note that the external control signal can be high active, meaning that it is on when high and off when low, or low active, meaning that it is on when low and off when high, and this is predetermined by the user.

[0004] However, if the control device is started before the host computer, depending on the state of the external control signal when the host computer is not started, the control device may interpret this as an ON (lighting command) and accidentally turn on the light irradiation device. For example, as shown in Figure 5, if the external control signal is set to low active in the host computer and the state of the external control signal is low when the host computer is not started, after the control device is started up and before the host computer starts up, the external control signal will be low, so the control device will mistakenly interpret this as a lighting command, resulting in the above-mentioned problem. The same applies when the external control signal is set to high active and the state of the external control signal is high when the host computer is not started up (see Figure 6).

[0005] To address this issue, for example, if the state of the external control signal in the host computer is low before it is started, it may be possible to simply set the external control signal to high active.

[0006] However, due to noise, lighting control programs in the host computer, etc., it may not be possible to change the active attribute related to high / low of the external control signal, and even if it were possible to change it, it would impose a burden on the user. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2017-033736 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0008] The present invention has been made in view of such problems, and aims to prevent the light irradiation device from being accidentally turned on at startup in a light irradiation system configured so that the host computer can turn on the light irradiation device via a control device, regardless of whether the control device or the host computer is started first. [Means for solving the problem]

[0009] That is, the light irradiation system according to the present invention comprises a light irradiation device that irradiates a workpiece with light for inspection or exposure, and a control device that controls the on / off of the light irradiation device based on an external control signal that takes two values, high / low, When the external control signal is low active, the control device controls the light irradiation device to be in an off state after startup until it detects a high value as the external control signal; When the external control signal is high active, the control device controls the light irradiation device to be in an off state after startup until it detects a low value as the external control signal.

[0010] If the control device accepts input of an active attribute indicating whether the external control signal is low active or high active, the user can input the active attribute of the external control signal into the control device to register or change it. Therefore, for example, even if a host computer or program with a different active attribute is changed, the user can handle it on their own without having to request the manufacturer to change the settings of the control device, thereby improving convenience. [Effects of the Invention]

[0011] According to the present invention, the control device maintains the light irradiation device in an off state regardless of the value of the external control signal until the host computer is started up, thereby preventing the light irradiation device from being accidentally turned on during that time. Furthermore, since the control device can reliably determine whether a light is turned on or off after the host computer is started, there is no problem with conventional control. Furthermore, the present invention can achieve the effect of being realized by simply changing the software in the control device, without having to replace the existing light irradiation system. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic electrical circuit diagram showing the overall configuration of a light irradiation system according to one embodiment of the present invention. [Figure 2] 4 is a flowchart showing the operation of the control device in the embodiment. [Figure 3] 10 is a timing chart showing the timing of turning on / off the light irradiation device when the external control signal is low active in the embodiment. [Figure 4] 10 is a timing chart showing the timing of turning on / off the light irradiation device when the external control signal is high active in the embodiment. [Figure 5] 10 is a timing chart showing the timing of turning on / off the light irradiation device when an external control signal is low active in a conventional light irradiation system. [Figure 6]10 is a timing chart showing the timing of turning on / off a light irradiation device when an external control signal is high active in a conventional light irradiation system. DETAILED DESCRIPTION OF THE INVENTION

[0013] An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the light irradiation system 100 according to this embodiment includes a light irradiation device 1 that emits inspection light used for, for example, surface inspection of various workpieces, and a control device 2 that controls the lighting of the light irradiation device 1.

[0014] The light irradiation device 1 includes an LED circuit 1A in which LEDs 12 serving as light sources are connected in series or parallel. There are various types of light irradiation devices 1, depending on the purpose of the inspection, such as a line type in which the LEDs 12 are arranged in a straight line, a ring type in which the LEDs 12 are arranged in a circular ring, or a surface-emitting type in which the LEDs 12 are arranged in a plane. The light irradiation device 1 includes a positive terminal 13 that supplies current to the LED circuit 1A and a negative terminal 14 that returns the current that has flowed through the LED circuit 1A to ground.

[0015] The control device 2 includes a constant voltage power supply 21 that supplies current to the LED 12 , a switching element 22 that turns the current on and off, and a control circuit 23 that drives the switching element 22 .

[0016] The constant voltage power supply 21 is an AC / DC converter connected to a commercial power source to convert alternating current into direct current, and its output terminal is connected via an electric cable to the positive terminal 13 of the light irradiation device 1. A large-capacity auxiliary current supply capacitor 24 is provided in the current supply line between this output terminal and the positive terminal 13 to supply auxiliary current when lighting the LED 12, improve the lighting start-up characteristics, and prevent the output voltage of the constant voltage power supply 21 from dropping instantaneously.

[0017] The switching element 22 is, for example, an FET that turns on / off the current supplied from the constant voltage power supply 21 to the LED 12. Specifically, the drain terminal (input terminal) of this switching element 22 is connected to the minus terminal 14 of the light irradiation device 1, and the source terminal (output terminal) is connected to ground via a current limiting resistor 25. A binary signal is input to the gate terminal (control terminal) of the switching element 22, thereby turning on / off the current supplied from the constant voltage power supply 21 to the LED 12. Note that the switching element 22 is not limited to an FET and can also be configured as, for example, a transistor, and the location of the switching element 22 is not limited to the cathode side of the LED 12, but may be the anode side.

[0018] The control circuit 23 is a so-called microcomputer equipped with a CPU (not shown), a memory (not shown), an input port 231, an output port 232, etc. The input port 231 is connected to an external host computer 200 used by a user, and the output port 232 is connected to the gate terminal of the switching element 22.

[0019] When an external control signal for turning the LED 12 ON (lighting up) / OFF (extinguishing) is input from the host computer 200, the control circuit 23 converts the external control signal into an internal control signal using logic defined in the program, and outputs this internal control signal to the gate terminal of the switching element 22, causing the LED 12 to emit light in strobe mode or PWM mode. The control circuit 23 may be configured using an FPGA or PLD. Next, the operation of the control circuit 23 will be described in detail with reference to the flowchart shown in FIG.

[0020] When the control circuit 23 is powered on and activated, in the initial state (step S1), the control circuit 23 sets the value of the internal control signal to a value that turns off the LED 12, i.e., a value that turns off the switching element 22 (here, for example, LOW) (step S2).

[0021] Meanwhile, the active attribute of the external control signal, that is, whether high active or low active, is recorded in a predetermined area of ​​the memory, and the control circuit 23 refers to this memory to determine the active attribute of the external control signal (step S3).

[0022] The input port 231 is provided with a channel for receiving input of a signal indicating the active attribute of an external control signal, and is configured so that the active attribute in the memory can be changed from the outside by specifying and inputting the active attribute into this channel, for example, by operating the input panel of the control device 2 or by communication from the host computer 200.

[0023] Next, if the external control signal is low active, the control circuit 23 turns off the switching element 22 and keeps the LED 12 in the off state until it detects a high value for the external control signal, or if the external control signal is high active, until it detects a low value for the external control signal (step S4).

[0024] After detection, the control circuit 23 outputs an internal control signal in accordance with the external control signal to turn on / off the LED 12 (step S5). Specifically, if the external control signal is low active, the control circuit 23 inverts the value of the external control signal to generate the internal control signal. On the other hand, if the external control signal is high active, the control circuit 23 sets the value of the external control signal as the value of the internal control signal.

[0025] Therefore, according to the above-described configuration, as shown in Figures 3 and 4, the light irradiation device 1 is maintained in an off state until the host computer 200 is started up, regardless of the value of the external control signal, thereby preventing accidental lighting during that time. Furthermore, since the control device 2 can reliably determine the on / off command after the host computer 200 is started up, there is no problem with the conventional control. Furthermore, there is an advantage that this can be achieved simply by changing the software in the control device, without having to replace the existing light irradiation system.

[0026] In addition, since the active attribute of the external control signal can be registered and changed by the user, even if the active attribute is changed to a different host computer or program, the user can handle it on their own without having to ask the manufacturer to change the settings of the control device, thereby improving convenience.

[0027] The present invention is not limited to the above-described embodiment. For example, the circuit configuration can be changed as appropriate, and a laser or a filament lamp can be used as the light source of the light irradiation device.

[0028] Furthermore, the present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the spirit of the invention, such as appropriately combining some of the configurations. [Explanation of symbols]

[0029] 100... Light irradiation system 1...Light irradiation device 2. Control device

Claims

1. The apparatus comprises a light irradiation device that irradiates a workpiece with light for inspection or exposure, and a control device that controls the on / off of the light irradiation device based on an external control signal that takes two values, high and low; When the external control signal is low active, the control device controls the light irradiation device to be in an off state after startup until it detects a high value as the external control signal; A light irradiation system characterized in that, when the external control signal is high active, the control device controls the light irradiation device to be in an off state after startup until it detects a low value as the external control signal.

2. 2. The light irradiation system according to claim 1, wherein the control device receives an input of an attribute signal indicating whether the external control signal is low active or high active.

3. The light irradiation device that irradiates the workpiece with light for inspection or exposure is turned on / off based on an external control signal that takes two values, high / low, When the external control signal is low active, after startup, the light irradiation device is controlled to be in an off state until a high value is detected as the value of the external control signal; When the external control signal is high active, the control device controls the light irradiation device to be in an off state after startup until the external control signal is detected to be low.

4. A method for controlling the on / off of a light irradiation device that irradiates a workpiece with light for inspection or exposure based on an external control signal that takes two values, high and low, comprising: When the external control signal is low active, after startup, the light irradiation device is controlled to be in an off state until a high value is detected as the value of the external control signal; A control method characterized in that, when the external control signal is high active, the light irradiation device is controlled to be in an off state after startup until a low value is detected as the value of the external control signal.

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