JP7428881B2 - Lighting circuit and optical information reading device - Google Patents

Description

The present invention relates to an illumination circuit for an optical information reading device and an optical information reading device that optically reads optical information such as an information code irradiated with illumination light.

A portable device that optically reads optical information by shining illumination light on information codes (barcodes, QR codes (registered trademark), etc.) and character information, and receiving the reflected light. Optical information reading devices are used in various environments, such as in relatively dark warehouses and relatively bright stores, so the required illuminance of illumination light differs depending on the environment. Generally, a method is adopted in which the illuminance of the illumination light is controlled by the lighting time of the LED, etc., but if the current flowing through the LED etc. is constant, the exposure will be long in a dark place, and the reading performance will be affected by camera shake etc. may worsen. On the other hand, in order to read information codes in the dark or at long distances, the current flowing through LEDs, etc. is increased or the number of LEDs, etc. is increased. This results in unnecessary power consumption. Furthermore, if the illumination pulse width is narrow, the blinking state tends to be dazzling, making it visually unpleasant. This kind of problem also occurs with stationary optical information reading devices, and even when reading information codes, etc. that are sequentially conveyed within the reading field, depending on the state of the display surface on which the information codes, etc. are attached, the illumination It may be desirable to vary the intensity of the light.

For this reason, an optical information reading device has been proposed in which the illuminance of illumination light can be changed by, for example, PWM control of LEDs for illumination light or by increasing or decreasing the number of LEDs that are lit. As such an optical information reading device, for example, an optical information reading device disclosed in Patent Document 1 listed below is known.

Japanese Patent Application Publication No. 2018-147522

By the way, in a configuration in which the illuminance of the illumination light is switched by PWM control of the LED for illumination light, the input current input from the illumination capacitor to the illumination light source increases rapidly at the start of irradiation, causing an instantaneous drain on the battery (power supply). load fluctuations will occur. In order to suppress this instantaneous load fluctuation of the battery, it is necessary to suppress the input current input from the lighting capacitor to the lighting light source. For this reason, the circuit board installed in the optical information reading device is generally equipped with a booster circuit that boosts the charging voltage charged from the battery to the lighting capacitor, and an input that keeps the input current below a certain value. A current limiting circuit, a constant current circuit for keeping the LED current for illumination light constant, etc. are implemented.

However, in the circuit board that switches illuminance as described above, it is necessary to make the boost voltage value, input limit current value, and LED current value variable depending on the illuminance condition, and many discrete components are mounted to configure them. Therefore, there is a problem that it becomes difficult to miniaturize the circuit board.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a lighting circuit that can switch the illuminance of illumination light while preventing instantaneous load fluctuations in the power supply. It is an object of the present invention to provide a configuration that can reduce the size of a circuit board to be mounted.

In order to achieve the above object, the invention described in claim 1 of the claims is as follows:
An illumination circuit (40) that switches the illuminance of illumination light emitted from the illumination light source (31, 31a, 31b) according to an input switching instruction,
a boost control unit (43) for boosting the charging voltage charged to the capacitor (32) from the power source (29) by PWM control;
a monitoring unit (42) that monitors the voltage value of the capacitor;
a current value setting unit (45, 46) for setting a current value flowing through the illumination light source to a predetermined current setting value when power is supplied from the capacitor to the illumination light source in accordance with a predetermined irradiation instruction;
The voltage value of the capacitor monitored by the monitoring unit becomes a predetermined voltage value specified from the switching instruction, and the input current value to the capacitor is limited to a predetermined current limit value specified from the switching instruction. an illuminance control unit (41) that performs PWM control on the boost control unit and controls the current value setting unit so that the predetermined current setting value is switched in accordance with the switching instruction;
It is characterized by having the following.
Note that the reference numerals in parentheses above indicate correspondence with specific means described in the embodiments described later.

In the first aspect of the invention, the charging voltage charged to the capacitor from the power source is boosted by PWM control of the boost control section, and the voltage value of this capacitor is monitored by the monitoring section. Furthermore, the current value that flows through the illumination light source when power is supplied from the capacitor to the illumination light source in response to a predetermined irradiation instruction is set to a predetermined current setting value by the current value setting section. Then, the voltage value of the capacitor monitored by the monitoring unit becomes a predetermined voltage value specified from the switching instruction, and the input current value to the capacitor is limited to the predetermined current limit value specified from the switching instruction. The boost control section is subjected to PWM control by the illuminance control section. Further, the current value setting section is controlled by the illuminance control section so that the predetermined current setting value is switched according to the switching instruction.

Thereby, the value of the current flowing through the illumination light source can be switched in accordance with the input switching instruction, so that the illuminance of the illumination light can be switched. Further, since the input current value to the capacitor is limited to a predetermined current limit value specified from the switching instruction, it is possible to prevent instantaneous load fluctuations in the power supply. In particular, the boost control section, monitoring section, current setting section, and illuminance control section provided in the lighting circuit can switch the illuminance and prevent instantaneous load fluctuations in the power supply. The number of discrete components mounted to configure circuits, input current limiting circuits, LED constant current circuits, etc. can be reduced. Therefore, it is possible to reduce the size of the circuit board on which the lighting circuit that can switch the illuminance of the illumination light is mounted while preventing the occurrence of instantaneous load fluctuations in the power supply.

In the invention of claim 2, the illumination light source includes a plurality of light emitting elements, and the switching instruction includes information for individually placing the plurality of light emitting elements into an irradiation state or a non-irradiation state. This not only makes it possible to switch the illuminance of the illumination light by changing the number of light emitting elements that enter the irradiation state in accordance with the switching instruction, but also allows the above-mentioned predetermined voltage to be changed when the number of light emitting elements that enter the irradiation state is small. By generating the switching instruction to reduce the value, it is possible to reduce power consumption.

In the invention of claim 3, when the illumination light is irradiated from the illumination light source toward the optical information while the illuminance is switched according to the switching instruction input to the illumination circuit, the optical information is An optical information reading device is realized in which the optical information is read by receiving the reflected light from the . As a result, it is possible to realize an optical information reading device that can reduce the size of the circuit board on which the lighting circuit that can switch the illuminance of the illumination light is mounted, while preventing the occurrence of instantaneous load fluctuations in the power supply. .

FIG. 1 is a perspective view showing an optical information reading device according to a first embodiment. FIG. 2 is a perspective view of the optical information reading device of FIG. 1 viewed from the back side. 2 is a block diagram schematically illustrating the electrical configuration of the optical information reading device of FIG. 1. FIG. 4 is a circuit block diagram schematically illustrating the electrical configuration of the illumination section in FIG. 3. FIG. 3 is a chart explaining the relationship between each mode and an output voltage setting value, an input current limit value, and a light source current setting value.

[First embodiment]
DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of an illumination circuit according to the present invention and an optical information reading device equipped with the illumination circuit will be described below with reference to the drawings.
The optical information reading device 10 according to the present embodiment is a portable information processing terminal that optically reads optical information such as information codes (barcodes, QR codes (registered trademark), etc.) and character information.

As shown in FIGS. 1 and 2, the casing 11 that constitutes the outer shell of the optical information reading device 10 is formed into a substantially thin plate shape, and the surface 11a has a narrow frame (narrow bezel). An enlarged display screen 24a is arranged so that the display screen 24a has a larger size than the other. Further, as shown in FIG. 2, a reading port 12 is provided on one side in the longitudinal direction of the back surface 11b of the casing 11 for taking in reflected light from an information code or the like irradiated with illumination light into the casing 11. A battery cover 13 is attached to the other longitudinal side.

Next, the electrical configuration of the optical information reading device 10 will be explained with reference to FIG. 3.
As shown in FIG. 3, the optical information reading device 10 includes a control unit 21 that controls the overall control, a storage unit 22 consisting of a semiconductor memory, etc., an imaging unit 23 configured as a camera, and an imaging field of view by the imaging unit 23. An illumination unit 24 that emits illumination light, a touch panel 25 whose display content is controlled by the control unit 21, an operation unit 26 that outputs signals to the control unit 21 in response to touch operations and key operations on the touch panel 25, and for communicating with host devices, etc. A communication section 27, a power supply section 28, a battery 29, and the like are provided.

In the optical information reading device 10 configured as described above, when the reading process is started by the control unit 21 in response to a predetermined operation performed on the operation unit 26 when reading an information code, etc., the reading process starts. By imaging (receiving) the reflected light from the information code, etc. irradiated with the illumination light of the illumination unit 24 through the mouth 12, in the imaging unit 23, processing for decoding the imaged information code, etc. is performed. Ru. In particular, in this embodiment, the illumination section 24 is used when the imaging section 23 takes an image, taking into account reading in a dark place, reading in a bright place, reading at a long distance, reading at a short distance, low power consumption, etc. The illuminance of the emitted illumination light can be switched to three levels.

Specifically, there is a high power mode in which the illuminance is switched to the highest level so that reading can be performed reliably in the dark or at a distance, and a high power mode in which the illuminance is switched to the lowest level to reduce power consumption. Three modes are available for user selection: power save mode and standard mode, which has an illuminance between high power mode and power save mode and assumes reading in bright light or at close range. ing.

Therefore, the illumination unit 24 according to the present embodiment has three levels of illumination intensity (high power mode, standard mode) based on a command input as a switching instruction from the control unit 21 in response to a mode selection operation by the user. , power save mode). Note that the default mode is set to standard mode. In particular, in this embodiment, the illumination unit 24 is capable of switching the illuminance of the illumination light, and inputs the input to the capacitor 32 to prevent instantaneous load fluctuations in the battery 29 at the start of illumination light irradiation. The current value is configured to be limitable.

Hereinafter, the characteristic configuration of the lighting circuit 40 and the like in the lighting section 24 according to this embodiment will be described in detail with reference to FIG. 4.
As shown in FIG. 4, the illumination section 24 mainly includes an illumination light source 31, an illumination capacitor 32, switch elements 33a to 33e, and an illumination circuit 40.

The illumination light source 31 includes two LEDs 31a and LED 31b as a plurality of light emitting elements, and the LED 31a is supplied with power from the capacitor 32 when the switch element 33c is in the ON state and the switch element 33a is in the OFF state. The reading port 12 is arranged so as to irradiate the field of view to be imaged by the imaging unit 23 with illumination light. In addition, when the switch element 33c is in the ON state and the switch element 33b is in the OFF state, the LED 31b is supplied with power from the capacitor 32, so that the LED 31b emits illumination light into the imaging field of view by the imaging unit 23 through the reading port 12. It is arranged to irradiate.

That is, when emitting illumination light, the illumination light source 31 can be switched between a case where both the LED 31a and the LED 31b are in the irradiation state, and a case where one of the LED 31a and the LED 31b is in the irradiation state and the other is in the non-irradiation state. configured. In this embodiment, in the high power mode described above, both LED 31a and LED 31b are in the irradiation state, and in the standard mode and power save mode, only one LED (for example, only LED 31a) is in the irradiation state.

The switch element 33d is controlled by the lighting circuit 40 and functions to boost the charging voltage charged to the capacitor 32 from the battery 29 via the coil 34 and the diode 35. The charging voltage of the capacitor 32 is monitored in the lighting circuit 40 using two resistors 36a and 36b. Further, the switch element 33e, together with a resistor 37 and an operational amplifier 46 of a lighting circuit 40 described later, provides a constant current for setting the current value flowing through the illumination light source 31 to a predetermined current setting value (hereinafter also referred to as a light source current setting value). It constitutes a circuit. In this embodiment, the light source current set value in the power save mode is set to be smaller than the light source current set value in the standard mode, thereby reducing power consumption.

The illumination circuit 40 is a circuit for switching the illuminance of the illumination light emitted from the illumination light source 31 in response to a switching instruction input from the control unit 21. This lighting circuit 40 mainly includes a CPU 41, an ADC 42, a PWM 43, a GPIO 44a, a GPIO 44b, a DAC 45, and an operational amplifier 46.

The ADC 42 functions as a monitoring unit that outputs a digital signal to the CPU 41 according to the voltage value of the capacitor 32 monitored using the resistors 36a and 36b. The PWM 43 is controlled by the CPU 41 so that the frequency and duty ratio are adjusted so that the voltage value of the capacitor 32 monitored using the ADC 42 is directed toward a predetermined voltage value (hereinafter also referred to as output voltage setting value). It functions as a boost control section that performs PWM control (switching control) on the switch element 33d so that the voltage is boosted. In particular, in order to prevent the occurrence of instantaneous load fluctuations in the battery 29, the PWM 43 adjusts the input current value to the capacitor 32 to a predetermined current limit value (hereinafter referred to as input current limit value) according to the adjustment of the frequency and duty ratio by the CPU 41. (also called current limit value).

The GPIO 44a is a general-purpose input/output port for switching the LED 31a between an irradiation state and a non-irradiation state, and the GPIO 44b is a general-purpose input/output port for switching the LED 31b between an irradiation state and a non-irradiation state. The GPIO 44a is connected to the switch element 33a, and is configured such that the CPU 41 outputs a signal for turning the switch element 33a on when the LED 31a is in a non-irradiation state. The GPIO 44b is connected to the switch element 33b, and is configured such that the CPU 41 outputs a signal for turning on the switch element 33b when the LED 31b is in a non-irradiation state.

The DAC 45 and the operational amplifier 46 function as a current value setting unit for setting the current value flowing through the illumination light source 31 to the light source current setting value, and acquire a digital signal from the CPU 41 according to the predetermined current setting value. The DAC 45 converts it into an analog signal and outputs it as a DAC setting value to the + input terminal of the operational amplifier 46, so that the value of the current flowing through the illumination light source 31 is set to the light source current setting value.

The CPU 41 controls the PWM 43 and the like to switch the output voltage setting value, input current limit value, and light source current setting value described above in response to a command input as the switching instruction from the control unit 21 via the I2C bus 47. This functions as an illuminance control section that switches the illuminance of the illumination light from the illumination light source 31.

Next, a description will be given of the processing performed in the lighting circuit 40 when one of the high power mode, standard mode, and power save mode is selected by the user's selection operation in the lighting unit 24 configured as described above. . Note that in this embodiment, as illustrated in FIG. 5, the output voltage setting value, input current limit value, and light source current setting value to be set are determined in advance in correspondence with the high power mode, standard mode, and power save mode. It is assumed that

When the high power mode is selected by a user who performs reading work in a dark place, a command for selecting the high power mode is input from the control unit 21 to the CPU 41 via the I2C bus 47 as a switching instruction. Upon receiving this command, the CPU 41 boosts the voltage value of the capacitor 32 monitored using the ADC 42 toward 10V (see the output voltage setting value of the high power mode in FIG. 5), and increases the input current value to the capacitor 32. The switching element 33d is controlled by PWM so that the input current limit value is limited to 500 mA (see the input current limit value in the high power mode in FIG. 5). Further, the CPU 41 turns the switch element 33a and the switch element 33b into the OFF state so that when the switch element 33c is in the ON state, power is supplied from the capacitor 32 to both the LED 31a and the LED 31b. Further, the CPU 41 sets the DAC setting value outputted from the DAC 45 to the + input terminal of the operational amplifier 46 so that the current value flowing through the illumination light source 31 is 700 mA (see the light source current setting value in high power mode in FIG. 5). do.

As a result, when the switch element 33c controlled by the control unit 21 is turned on as a predetermined irradiation instruction in response to the start of the reading process in response to the reading operation by the user, both the LED 31a and the LED 31b to which power is supplied from the capacitor 32 are turned on. is illuminated, making it possible to reliably read in the dark or at a long distance. At this time, since the input current value to the capacitor 32 is limited to the input current limit value (500 mA), the input current input from the capacitor 32 to the illumination light source 31 does not increase rapidly.

Further, when the power save mode is selected by a user who wants to extend the battery life and use the optical information reading device 10 for a long time, a command for selecting the power save mode is sent from the control unit 21 to the I2C bus 47 as a switching instruction. It is input to the CPU 41 via. Upon receiving this command, the CPU 41 boosts the voltage value of the capacitor 32 monitored using the ADC 42 toward 5V (see the output voltage setting value of the power save mode in FIG. 5), and increases the input current value to the capacitor 32. The switching element 33d is controlled by PWM so that the input current limit value is limited to 100 mA (see the input current limit value in the power save mode in FIG. 5). Further, when the switch element 33c is in the ON state, the CPU 41 turns the switch element 33a into the OFF state and turns the switch element 33b into the ON state so that power is supplied from the capacitor 32 only to the LED 31a. Further, the CPU 41 sets the DAC setting value outputted from the DAC 45 to the + input terminal of the operational amplifier 46 so that the current value flowing through the illumination light source 31 is 100 mA (see the light source current setting value in power save mode in FIG. 5). do.

As a result, when the switch element 33c controlled by the control unit 21 is turned on as a predetermined irradiation instruction in response to the start of the reading process in response to the reading operation by the user, only the LED 31a to which power is supplied from the capacitor 32 is in the irradiation state. Therefore, the value of the current flowing through the illumination light source 31 is also reduced to the light source current setting value (100 mA), so that power consumption can be reduced while making reading possible in a relatively easy-to-read environment. Even in this case, since the input current value to the capacitor 32 is limited to the input current limit value (100 mA), the input current input from the capacitor 32 to the illumination light source 31 does not increase rapidly.

Furthermore, when the user selects the standard mode, a command for selecting the standard mode is input from the control unit 21 to the CPU 41 via the I2C bus 47 as a switching instruction. Upon receiving this command, the CPU 41 boosts the voltage value of the capacitor 32 monitored using the ADC 42 toward 5V (see the standard mode output voltage setting value in FIG. 5), and increases the input current value to the capacitor 32. The switching element 33d is controlled by PWM so that the input current is limited to 200 mA (see the standard mode input current limit value in FIG. 5). Further, when the switch element 33c is in the ON state, the CPU 41 turns the switch element 33a into the OFF state and turns the switch element 33b into the ON state so that power is supplied from the capacitor 32 only to the LED 31a. Further, the CPU 41 sets the DAC setting value output from the DAC 45 to the + input terminal of the operational amplifier 46 so that the current value flowing through the illumination light source 31 is 300 mA (see the standard mode light source current setting value in FIG. 5). .

As a result, when the switch element 33c controlled by the control unit 21 is turned on as a predetermined irradiation instruction in response to the start of the reading process in response to the reading operation by the user, only the LED 31a to which power is supplied from the capacitor 32 is in the irradiation state. This makes it possible to read in bright light and at close range. Even in this case, since the input current value to the capacitor 32 is limited to the input current limit value (200 mA), the input current input from the capacitor 32 to the illumination light source 31 does not increase rapidly.

As described above, in the lighting circuit 40 according to the present embodiment, the charging voltage charged to the capacitor 32 from the battery (power source) 29 is boosted by PWM control of the PWM 43, and the voltage value of the capacitor 32 is adjusted using the ADC 42. will be monitored. Further, when power is supplied from the capacitor 32 to the illumination light source 31 in response to a predetermined irradiation instruction, the value of the current flowing through the illumination light source 31 is set to a predetermined current value using a DAC 45 and an operational amplifier 46 that function as a current value setting section. value (light source current setting value). Then, the monitored voltage value of the capacitor 32 becomes a predetermined voltage value (output voltage setting value) specified from the switching instruction, and the input current value to the capacitor 32 becomes a predetermined current limit value (input voltage setting value) specified from the switching instruction. The PWM 43 is PWM-controlled by the CPU 41 so that the current is limited to the current limit value (current limit value). Further, the DAC 45 and the operational amplifier 46 are controlled by the CPU 41 so that the predetermined current setting value is switched in response to a switching instruction.

Thereby, the value of the current flowing through the illumination light source 31 can be switched in accordance with the input switching instruction, so that the illuminance of the illumination light can be switched between the standard mode and the power save mode. Furthermore, since the input current value to the capacitor 32 is limited to the input current limit value specified from the switching instruction, it is possible to prevent instantaneous load fluctuations in the battery 29 from occurring. In particular, since the PWM 43, ADC 42, DAC 45, operational amplifier 46, and CPU 41 provided in the lighting circuit 40 can switch the illuminance and prevent instantaneous load fluctuations on the battery 29, a booster circuit or The number of discrete components mounted to configure the input current limiting circuit, LED constant current circuit, etc. can be reduced. Therefore, it is possible to reduce the size of the circuit board on which the illumination circuit 40, which can switch the illuminance of the illumination light, is mounted while preventing the occurrence of instantaneous load fluctuations in the battery 29.

In the present embodiment, illumination light is irradiated from the illumination light source 31 toward optical information such as an information code while the illumination intensity is switched according to a switching instruction inputted to the illumination circuit 40. At this time, an optical information reading device 10 is realized in which the optical information is read by receiving reflected light from the optical information. Thereby, an optical information reading device 10 is realized that can reduce the size of the circuit board on which the illumination circuit 40 that can switch the illuminance of the illumination light is mounted while preventing the occurrence of instantaneous load fluctuations in the battery 29. be able to.

In particular, in this embodiment, the illumination light source 31 includes two LEDs 31a and LED 31b as a plurality of light emitting elements, and the switching instruction includes information for individually setting the LED 31a and the LED 31b to an irradiation state or a non-irradiation state. included. Specifically, the command input as a switching instruction to switch to high power mode includes information for setting both LED 31a and LED 31b to the irradiation state, and the command input as a switching instruction to switch to high power mode includes information for setting both LED 31a and LED 31b to the irradiation state. The command input as an instruction includes information for setting only one LED to the irradiation state. The output voltage setting value set by the command for standard mode or power save mode (5V in the example in Figure 5) is different from the output voltage setting value set by the command for high power mode (10V in the example in Figure 5). ) is set to be lower than

This not only makes it possible to switch the illuminance of the illumination light by changing the number of light emitting elements that enter the irradiation state in accordance with the switching instruction, but also sets the output voltage as described above when the number of light emitting elements that enter the irradiation state is small. By generating the switching instruction to decrease the value, it is possible to reduce power consumption.

Note that the present invention is not limited to the above-described embodiments, and may be embodied as follows, for example.
(1) The illumination circuit 40 according to the present invention is not limited to being employed in a portable optical information reading device 10 that optically reads optical information such as information codes and character information; The present invention may be employed in a portable optical information reading device that reads information, or may be employed in an optical information reading device that has other functions. Further, the illumination circuit 40 according to the present invention may be employed in a stationary optical information reading device, or may be employed in a device that requires switching of illuminance depending on the illumination light emitted.

(2) The illumination unit 24 is not limited to being configured so that the illuminance of the illumination light emitted can be switched to three levels, but may be configured to be switchable to two levels or four or more levels. Furthermore, the illumination light source 31 is not limited to having two LEDs 31a and 31b, but may be configured to include three or more light emitting elements such as LEDs. In this case, the illumination circuit 40 may switch the illuminance of the illumination light to be irradiated by changing the number of light emitting elements set in the irradiation state in each mode, or adjust the current value flowing through each light emitting element to the above-mentioned DAC setting value. The illuminance of the irradiated illumination light may be changed by changing the illumination intensity according to the illumination light.

(3) The output voltage setting value, input current limit value, and light source current setting value that should be set corresponding to each mode are not limited to those set in advance as illustrated in FIG. It may be set in advance, or may be changed as appropriate according to a changing operation by the user.

(4) The mode selection operation by the user may be performed in response to a predetermined touch operation on the touch panel 25, or, for example, by reading an information code for mode selection, a mode corresponding to the read information code is selected. It may be done as follows.

10... Optical information reading device 21... Control section 24... Lighting section 29... Battery (power source)
31...Illumination light source 31a, 31b...LED (light emitting element)
32...Capacitor 40...Lighting circuit 41...CPU (illuminance control unit)
42...ADC (monitoring section)
43...PWM (boost control section)
45...DAC (current value setting section)
46...Operational amplifier (current value setting section)

Claims (3)

A lighting circuit that switches illuminance of illumination light emitted from an illumination light source in accordance with an input switching instruction,
a boost control unit for boosting the charging voltage charged to the capacitor from the power supply by PWM control;
a monitoring unit that monitors the voltage value of the capacitor;
a current value setting unit for setting a current value flowing through the illumination light source to a predetermined current setting value when power is supplied from the capacitor to the illumination light source in accordance with a predetermined irradiation instruction;
The voltage value of the capacitor monitored by the monitoring unit becomes a predetermined voltage value specified from the switching instruction, and the input current value to the capacitor is limited to a predetermined current limit value specified from the switching instruction. an illuminance control unit that performs PWM control on the boost control unit and controls the current value setting unit so that the predetermined current setting value is switched in accordance with the switching instruction;
A lighting circuit comprising: The illumination light source includes a plurality of light emitting elements,
2. The lighting circuit according to claim 1, wherein the switching instruction includes information for individually setting the plurality of light emitting elements into an irradiation state or a non-irradiation state. An optical information reading device comprising the illumination circuit and illumination light source according to claim 1 or 2,
When the illumination light is irradiated from the illumination light source toward the optical information while the illuminance is switched according to the switching instruction input to the illumination circuit, reflection from the optical information An optical information reading device characterized in that the optical information is read by receiving light.

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