KR102074385B1 - Control apparatus and method for providing control signal thereof - Google Patents

Abstract

The control device of the present invention determines the motion state of the object in the device for detecting / recognizing the motion of the object using IRLED (Infrared LED) and PD (Photodiode) and provides an IRLED switching control signal suitable for the motion state. Such a control device is a light emitting diode driving control device, and includes a movement speed generating unit, a previous section average value generating unit, a state value generating unit, a control unit, and a light emitting diode switching control signal generating unit.

Description

Light emitting diode driving control device and its control signal providing method {CONTROL APPARATUS AND METHOD FOR PROVIDING CONTROL SIGNAL THEREOF}

The present invention relates to a drive control device, and more particularly, a light emitting diode drive control device for driving IRLEDs more efficiently in a device for detecting and recognizing the movement of an object using IRLED (Infrared LED) and PD (Photodiode); It relates to a control signal providing method thereof.

In the conventional motion detection / recognition technology, a method using a video camera has been mainly used. However, since the method of using a video camera in a mobile terminal consumes a lot of power, a method of using an IRLED and a PD has recently been preferred.

In the case of this method the emission of infrared light is carried out via the IRLED. In the presence of an object, infrared light reflected from the object is received by the PD. When the amount of reflected infrared light is measured, the approach of the object can be detected or the direction in which the object is moved can be recognized.

In implementing the above method, the IRLED is switched periodically regardless of the movement of the object. If the method of switching the IRLED is inefficient, there is a problem in that power consumption is increased.

An object of the present invention is to provide a light emitting diode driving control apparatus and a control signal providing method thereof that can reduce or minimize the power consumption of the IRLED.

In order to achieve the object of the present invention, a light emitting diode drive control apparatus,

A motion speed generation unit configured to receive an input signal and generate a motion speed signal of the object;

A previous section average value generator configured to compare the input signals received in the previous sections to generate a previous section average value;

A state value generator configured to generate a motion state value for the input signal based on the average value of the last section and setting values for the determination of the motion state of the object;

A controller configured to apply the set values to the state value generator and to generate the switching control signal frequency value by receiving the movement speed signal and the movement state value; And

And a light emitting diode switching control signal generator for generating a light emitting diode switching control signal in response to the switching control signal frequency value and applying the light emitting diode switching control signal to a driving unit for driving the light emitting diode.

According to an embodiment of the present disclosure, the input signal may be one or more photodiode signals.

According to an embodiment of the invention, the control unit,

A setting value register unit for storing frequency information, speed information, and time information as setting values for determining the motion state of the object;

A variable state frequency generator for generating a variable state frequency for a moving speed of the object according to the frequency information and the speed information applied from the set value register unit;

A constant state frequency generator for generating a constant state frequency by receiving frequency information related to a constant state from the set value register unit in the constant state frequency generation mode; And

And a multiplexer configured to output the variable state frequency or the constant state frequency as the switching control signal frequency value according to the motion state value.

According to an embodiment of the present disclosure, the multiplexer may further output the standby state frequency provided from the set value register unit as the switching control signal frequency value according to the motion state value.

According to an embodiment of the present invention, the state value generating unit,

A state determination threshold generation unit for generating a maximum and minimum state determination threshold in a state determination threshold generation mode, by receiving the average range of previous ranges applied from the previous range average value generation unit and a status determination threshold ratio applied from the control unit; And

And a state determination unit for determining a movement state of the input signal and generating the movement state value according to the time information and the maximum and minimum state determination thresholds applied from the controller.

According to an embodiment of the present invention, the filter unit for removing the noise included in the input signal may be further included in the front end of the movement speed generating unit and the previous section average value generating unit.

According to an embodiment of the present disclosure, the LED switching control signal may have different on / off periods in a standby state and a motion detection state.

According to an embodiment of the present disclosure, the on / off period in the motion detection state may be smaller than the on / off period in the standby state.

According to an embodiment of the present disclosure, the on / off period in the motion detection state may vary according to the motion state of the object.

In order to achieve the object of the present invention, a method of providing a light emitting diode driving control signal,

Receiving an input signal to generate a motion velocity signal of the object, and comparing the input signals received in the previous sections to generate an average value of the preceding section;

Generating a motion state value for the input signal according to the average value of the last section and set values for the determination of the motion state of the object;

Generating a switching control signal frequency value using the motion speed signal and the motion state value;

And generating a light emitting diode switching control signal according to the switching control signal frequency value and applying the same to the light emitting diode driver.

According to an embodiment of the present disclosure, the method may further include a filtering step of removing noise included in the input signal before generating the motion state value.

According to an embodiment of the present disclosure, the set values may include frequency information, speed information, and time information.

In order to achieve the object of the present invention, a motion detection and recognition device,

An infrared light emitting diode array unit for irradiating infrared rays to an object;

A photodiode array unit configured to receive the infrared rays reflected from the object and generate a current signal according to the received amount;

A photodiode signal processor for processing the current signal to generate a photodiode signal value represented as digital data;

A motion detection and recognition unit for recognizing the approach or movement direction of the object by using the photodiode signal value:

A light emitting diode driver for driving the infrared light emitting diode array unit in response to an applied switching control signal; And

And an infrared light emitting diode controller configured to generate a switching control signal according to the degree of movement of the object using the photodiode signal value.

According to the present invention, since the frequency of the IRLED switching control signal is controlled according to the motion state and the speed of the object, the power consumption of the IRLED is minimized or reduced while the detection / recognition precision is high.

1 is an exemplary block diagram of a motion sensing / recognition apparatus to which the present invention is applied;
2 is a diagram illustrating various arrangements of an IRLED and a PD in the motion detection / recognition device of FIG. 1;
3 is an exemplary waveform diagram of a general IRLED switching control signal;
4 is an exemplary waveform diagram of an IRLED switching control signal according to an embodiment of the present invention;
FIG. 5 is a diagram illustrating an output signal value of a PD according to the position and time of an object moved in the apparatus of FIG. 1;
6 is a graph illustrating an output signal value of an hourly PD according to a moving speed of an object in the apparatus of FIG. 1;
7 is an exemplary detailed block diagram of the IRLED controller of FIG. 1;
FIG. 8 is an exemplary detailed block diagram of the controller of FIG. 7;
9 is a diagram illustrating an approximation of an output characteristic of the previous section average value generation unit in FIG. 7;
10 is an exemplary detailed block diagram of a state value generator of FIG. 7;
FIG. 11 is a graph illustrating an operating characteristic of the variable frequency generator of FIG. 8.
FIG. 12 is a diagram schematically illustrating a graph approximating a change in state value and a change in switching control signal frequency according to FIG. 7, and
FIG. 13 exemplarily shows a graph approximating a change in another state value and a change in a switching control signal frequency according to FIG. 7; FIG.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present invention will be described, and descriptions of other parts will be omitted so as not to obscure the gist of the present invention.

1 is an exemplary block diagram of a motion sensing / recognition apparatus to which the present invention is applied.

Referring to FIG. 1, a motion detection and recognition device includes an infrared light emitting diode array unit 4, a photodiode array unit 2, a photodiode signal processor 100, a motion detection and recognition unit 200, and a light emitting diode driver. 400, and an infrared light emitting diode control unit 300.

The infrared light emitting diode array unit 4 irradiates infrared rays to an object. The infrared light emitting diode array unit 4 may include one or more IRLEDs.

The photodiode array unit 2 receives the infrared rays reflected from the object and generates a current signal according to the received amount. The photodiode array unit 2 may include one or more PDs.

The photodiode signal processor 100 processes the current signal to generate a photodiode signal value represented as digital data. The PD signal processing unit 100 may include a circuit element for converting a current signal into a voltage and then amplifying it, an ambient light removing device, and an analog-to-digital converter for converting the amplified voltage into digital data.

The motion detection and recognition unit 200 recognizes the approach or movement direction of the object by using the photodiode signal value.

The light emitting diode driver 400 drives the infrared light emitting diode array unit 4 in response to an applied switching control signal. The IRLED driver 400 may include a current / voltage generator for switching the IRLED array unit 4.

The infrared light emitting diode controller 300 generates a switching control signal according to the degree of movement of the object by using the photodiode signal value.

The infrared light emitting diode control unit 300 in the motion sensing and recognition device functions as a light emitting diode driving control device in an embodiment of the present invention.

The LED driving control device is included in a device for detecting and recognizing the movement of an object using IRLED (Infrared LED) and PD (Photodiode), to determine the movement state of the object and IRLED switching control signal frequency suitable for the movement state Create a value.

FIG. 2 illustrates various arrangements of IRLEDs and PDs in the motion sensing / recognition apparatus of FIG. 1. Here, the arrangement of the IRLED and the PD may be arranged in various forms in consideration of the purpose of use and the necessary functions. The arrangement in which the IRLED and the PD face each other is shown by reference numeral 21 in FIG. 2. The arrangement in which the IRLEDs are opposed between the plurality of PDs is indicated by reference numeral 22 in FIG. 2. The arrangement structure surrounded by the plurality of PDs in which the IRLEDs are installed in a triangular structure is indicated by reference numeral 23 in FIG. 2.

An arrangement structure surrounded by a plurality of PDs in which an IRLED is installed in a rectangular structure is indicated by reference numeral 24 of FIG. 2. An arrangement structure in which the PD exists between a plurality of IRLEDs installed in a straight line structure is indicated by reference numeral 25 in FIG. 2.

An arrangement structure in which the PD is surrounded by a plurality of IRLEDs installed in a rectangular structure is indicated by reference numeral 26 in FIG. 2.

In order to detect and recognize the movement of the object by using the IRLED and PD as shown in Figure 2 it is necessary to drive the IRLED control using the IRLED switching control signal so that the IRLED can emit light.

3 is an exemplary waveform diagram of a general IRLED switching control signal;

The switching control signal of FIG. 3 is a pulse signal having a relatively short on period and a relatively long off period. Power consumption increases when the IRLED keeps emitting light. Accordingly, as shown in the waveform signal of FIG. 3, the switching control signal is given in the form of a pulse signal having an ON / OFF period periodically.

When the IRLED emits light in the ON period, infrared rays reflected from the object are applied to the PD. The PD generates a current signal according to the amount of infrared light. The photodiode signal value displayed through the current signal is used to detect the movement of the object. The frequency of the switching control signal of FIG. 3 is determined in consideration of the maximum moving speed of the object to be recognized. That is, the frequency of the switching control signal of the IRLED is determined in a range that does not affect the recognition. However, as shown in FIG. 3, the switching control signal having a constant period is disadvantageous in terms of power consumption of the IRLED. That is, the IRLED emits light at a relatively high switching frequency even when an object has a slow moving speed or no object. As a result, since the switching control signal of the IRLED is generated at a constant frequency irrespective of the degree of movement of the object, even when the moving speed of the object is slow or there is no object, frequent driving of the IRLED is caused, resulting in waste of power consumption.

4 is an exemplary waveform diagram of an IRLED switching control signal according to an embodiment of the present invention.

Referring to FIG. 4, an IRLED switching control signal having a different frequency in each of the sections T1, T2, and T3 is shown.

The sections T1 and T3 are sections in a standby state. The section T2 is a section in a moving state. Even in the motion state, the generation frequency of the IRLED switching control signal varies depending on the degree of movement or the state of the object. That is, even within the period T2, the frequency of the IRLED switching control signal is variable. According to the IRLED switching control signal, there is an advantage of minimizing or reducing power consumption of driving the infrared light emitting diodes while increasing the detection and recognition accuracy.

The IRLED switching control signal is generated by a light emitting diode driving control device which is the infrared light emitting diode control unit 300.

FIG. 5 is a diagram illustrating an output signal value of a PD according to the position and time of an object moved in the apparatus of FIG. 1.

Referring to FIG. 5, when an object is outside the infrared light emitting range of the IRLED (1), the PD signal value is not the minimum value '0' due to the influence of incident and reflection of external light and the offset generated from the PD signal processor. Is output as a low value.

When the object moves and enters the infrared light emitting range of the IRLED (2), the amount of infrared light reflected by the PD increases, and the PD signal value also increases. In this case, the rate of change of the PD signal value also increases in proportion to the moving speed of the object.

In the state of ②, when the object enters further into the infrared light emitting range of the IRLED and the change of the reflection amount does not occur (③), the PD signal value maintains a constant output.

When the object moves and moves out of the infrared light emitting range of the IRLED (4), the amount of infrared light reflected by the PD decreases, thereby reducing the PD signal value.

If the object is completely out of the infrared light emitting range of the IRLED (⑤), a low value is output as in the case of ①.

The graph shown in the lower part of FIG. 5 shows results corresponding to the five cases as described above. The horizontal axis of the graph represents time and the vertical axis represents PD signal values.

6 is a graph exemplarily illustrating an output signal value of an hourly PD according to a moving speed of an object in the apparatus of FIG. 1.

Referring to FIG. 6, graphs G1, G2, and G3 are shown for three cases in relation to the moving speed of an object. In each of the graphs, the horizontal axis represents time and the vertical axis represents the PD signal value.

Assuming that the movement of the object is a medium speed based on the graph G2 of FIG. 6, the graph G1 represents a high speed case and the graph G3 represents a low speed case.

As in the case of 3 of FIG. 5, even when the object is within the infrared emission range of the IRLED, a section in which the PD signal value is kept constant occurs. In this case, since the rate of change of the PD signal value is low, it is not necessary to make the frequency of the IRLED switching control signal relatively high. On the other hand, in the case of (2) and (4) where the change in the PD signal value is large, it is necessary to increase the frequency of the IRLED switching control signal. This is because, in order to increase the accuracy of the detection and recognition related to the motion, the change in the PD signal value for the minute motion of the object must be measured more precisely. Since the accuracy of sensing and recognition is also affected by the speed of movement of the object, the higher the rate of change of the PD signal value, the higher the frequency of the IRLED's switching control signal. On the contrary, in case of ①, ③, ⑤ where the change of PD signal value is small, there is no problem in recognition even if the frequency of IRLED switching control signal is lowered.

In the embodiment of the present invention, the motion state and the speed of the object are determined and generated through the PD signal value. The frequency of the IRLED switching control signal is optimally adjusted for the motion and speed of the object. As a result, since the switching control signal is generated by the light emitting diode driving control device as the infrared light emitting diode control unit 300 as shown in FIG. 7, power consumption is reduced and accuracy of detection and recognition is increased.

FIG. 7 is an exemplary detailed block diagram of the IRLED controller of FIG. 1.

Referring to FIG. 7, the LED driving control apparatus as the IRLED controller 300 includes:

The filter unit 310 may include a filter section 310, a previous range average value generator 320, a motion speed generator 330, a state value generator 340, a controller 350, and a switching control signal generator 360. .

The motion velocity generator 330 receives an input signal which may be a PD signal value and generates a motion velocity signal of the object. The motion velocity signal is generated by calculating a rate of change of the PD signal value. As the moving speed of the object increases, the rate of change of the PD signal value increases. By using this characteristic, the motion velocity signal is generated.

The filter unit 310 removes noise included in the input signal.

The previous section average value generator 320 compares the input signals received in the previous sections to generate the previous section average value.

The state value generator 340 generates a movement state value for the input signal based on the average value of the last section and setting values for the determination of the movement state of the object.

The controller 350 applies the set values to the state value generator, and receives the movement speed signal and the movement state value to generate a switching control signal frequency value.

The switching control signal generator 360 generates a light emitting diode switching control signal in response to the switching control signal frequency value and applies it to the IRLED driver 400 driving the light emitting diode.

As described with reference to FIG. 4, the light emitting diode switching control signal is a signal that is optimally adjusted to the motion state and speed of an object.

8 is an exemplary detailed block diagram of the controller of FIG. 7.

Referring to FIG. 8, the control unit 350 includes a set value register unit 352, a variable state frequency generator 354, a constant state frequency generator 356, and a multiplexer 358.

 The setting value register unit 352 stores frequency information, speed information, and time information as setting values for the determination of the motion state of the object. The set value register section 352 includes a register controller 91 and a register 92 for storing the set values in a plurality of storage areas according to the control signal of the register controller 91.

Here, the set values are the maximum frequency, standby frequency, constant state frequency, minimum frequency, minimum movement speed, maximum movement speed, standby state determination time, constant state determination time, state determination threshold ratio, state determination threshold generation mode, and It may include an input set value such as a constant state frequency generation mode.

The variation state frequency generator 354 generates the variation state frequency with respect to the moving speed of the object according to the frequency information and the speed information applied from the set value register 352.

The constant state frequency generator 356 generates the constant state frequency by receiving frequency information related to the constant state from the set value register unit 352 in the constant state frequency generation mode. The constant state frequency generator 356 receives an input set value of a constant state frequency, a constant state frequency generating mode, and a variable state frequency to generate a frequency of an IRLED switching control signal for use in the constant state.

Here, the constant state frequency generation mode is a mode for selecting a method for generating a constant state frequency and is divided into a normal mode and an adaptive mode. When set to the normal mode, the set constant frequency is generated as an output. In the adaptive mode, a constant state frequency is generated as an output proportional to the variable state frequency value immediately before the state value changes to a constant state. The final output frequency of the fluctuation reflects the speed of movement of the object. The reason for using the adaptive mode is to reflect the moving speed of the object even if the IRLED switching frequency is lowered in a certain state. If the moving speed of the object is fast, the constant state is shortened in proportion to its speed. The moment the constant state ends and changes to the change state, the PD signal change is large. Therefore, if the IRLED switching frequency is too low, accurate movement of the object is difficult to detect.

The multiplexer 358 outputs the variable state frequency or the constant state frequency as the switching control signal frequency value according to the motion state value. In addition, the multiplexer 358 may output the standby state frequency provided from the set value register unit as the switching control signal frequency value according to the movement state value.

When generating the frequency of the switching control signal proportional to the speed of movement of the object, the maximum speed of the object in the applied system, the driving characteristics of the IRLED, the device characteristics of the analog circuit of the driving unit, etc. need to be taken into consideration. That is, such characteristics should be reflected in setting the maximum frequency for the switching control signal.

On the other hand, even if the movement speed of the object is slow, it is also necessary to set the minimum frequency to detect and recognize the object.

In addition, the standby frequency to be used in the standby state can also be set. When an object enters the standby state without an object, if the frequency of the switching control signal is too low in the standby state, the reaction time for detecting the movement of the object may be slow. As a result, since the recognition speed may be lowered, setting of the standby frequency is also necessary.

In the case of a constant state, the PD signal value is kept constant, similar to the standby state. Therefore, it is not necessary to perform IRLED switching at high speed as in the fluctuating state. However, because the object is moving, a frequency higher than the standby frequency may be needed. Reducing the IRLED switching frequency in certain states reduces the power consumption associated with driving the IRLED.

9 is a diagram illustrating an approximation of an output characteristic of the previous section average value generation unit in FIG. 7.

In FIG. 9, the horizontal axis represents time and the vertical axis represents PD signal values.

The section PD between the time points t1 and t2 indicates a previous section, and the time point t3 indicates a current time point. The graph GP1 indicates the PD signal value over time and the graph GP2 indicates the average value of the previous section. The previous section average value generating unit 320 generates an average value of the previous section PD that was before a predetermined time of the current PD signal value as shown in the graph GP2.

10 is an exemplary detailed block diagram of the state value generator of FIG. 7.

Referring to FIG. 10, the state value generation unit 340 may include a state determination unit 344 for determining a motion state of an object and a state determination threshold generation unit for generating a state determination threshold max and a state determination threshold min required for state determination. 342. The state determination threshold generation unit 342 receives the average value of the last section. In addition, the state determination threshold value generation unit 342 receives the state determination threshold value ratio and the state determination threshold value generation mode stored in the setting value register unit 352 in the control unit 350.

The state judgment threshold generation mode is divided into a normal mode and an adaptive mode. That is, the state determination threshold generation mode is a signal for selecting one of two methods for generating the state determination thresholds (max, min). First, in the normal mode, the variation value is calculated by multiplying the average value of the preceding section by the ratio of the state determination threshold. The state threshold value max is generated by adding the above variation value to the average value of the last section, and the state threshold value min is generated by subtracting the above variation value.

Secondly, in the adaptive mode, the variation value is calculated by multiplying the state determination threshold ratio by the difference value obtained by subtracting the average value of the previous section from the maximum value of the outputtable PD signal value. In the same manner as in the normal mode, the state judgment threshold value max is generated by adding the above variation value to the average value of the previous section, and the state judgment threshold value min is generated by subtracting the above variation value. Here, the reason for using the adaptive mode is to increase the width of the state determination threshold (max, min) in the state where the PD signal value is low, and to be insensitive to small PD signal value change, and to increase the state determination threshold (max) in the state where the PD signal value is high. , min) to make it sensitive to changes in relatively small PD signal values.

The state determination unit 344 receives the PD signal value, the state determination threshold value (max, min), the constant state determination time and the standby state determination time stored in the set value register of the controller. The standby state determination time may be set to be greater than the predetermined state determination time. The state value, which is the output of the state determination unit, may have three values, a standby state, a constant state, and a change state. The state determination unit 344 determines the state value by using the above-described input values.

If the PD signal value is maintained within the state determination threshold value (max, min) for more than the standby state determination time, it is determined as a standby state from thereafter.

If the PD signal value is maintained within the state determination threshold (max, min) for more than a predetermined state determination time, it is determined as a constant state from thereafter.

If the PD signal value is out of the state determination threshold (max, min), or is in a state other than the constant state and the standby state, it is determined to be a change state.

That is, the standby state indicates a state in which there is no object reflected or no movement of the object for a long time. The fluctuating state indicates a state in which the PD signal value changes as the object moves, and the constant state is a state in which the infrared reflectance is kept constant because the object is partially or entirely included within the emission range of the IRLED, as shown in ③ of FIG. 5. Indicates. In addition, even when the object is completely out of the IRLED emission range, it is determined to be in a constant state until it is determined to be in the standby state.

FIG. 11 is a graph illustrating an operating characteristic of the variable frequency generator of FIG. 8.

The variable frequency generator 354 shown in FIG. 8 generates the frequency of the IRLED switching control signal for use in the variable state. The variable frequency generator 354 receives, as input, a set maximum frequency, minimum frequency, movement speed min, and movement speed max. In addition, the variable frequency generator 354 receives the movement speed output from the movement speed generator 330 of FIG. 7. The variable frequency generator 354 outputs a minimum frequency when the input movement speed is less than or equal to the movement speed min value, and outputs a maximum frequency when the input movement speed is greater than or equal to the movement speed max. The variable frequency generator 354 generates a frequency proportional to the movement speed as shown in the graph VSF in the case of the movement speed min and the movement speed max.

FIG. 12 is a diagram illustrating a graph approximating a change in state value and a change in switching control signal frequency according to FIG. 7.

The graph of FIG. 12 approximates the change of the state value and the change of the IRLED switching control signal frequency according to the movement of the object. In the graph shown at the top of the figure, the horizontal axis represents time and the vertical axis represents PD signal values, respectively. On the other hand, in the graph shown at the bottom of the figure, the horizontal axis indicates time and the vertical axis indicates the frequency of the switching control signal, respectively.

Referring to FIG. 12, section A represents a standby state of an initial time. This section A means a state that has already been determined as a standby state and there is no entry of an object. In the case of the section A, the PD signal value is kept low and the average value of the immediately preceding section is output similarly to the PD signal value. The PD signal value is maintained within the status determination threshold (max, min) range. In this case, the output frequency up to time t1 becomes the standby state frequency, which is an input setting value.

A1 in the section B is a case where the object enters the IRLED emission range at a constant speed. In the case of a1 in the interval B, the PD signal value is increased and the rate of change is constant. In this case, the PD signal value is out of the state determination threshold (max, min) and changes from the standby state to the change state. In this fluctuation state, the fluctuation frequency is generated. The moving speed of the object is constant between the time points t1 and t2 of FIG. 12. Thus, the steady state frequency is constant as shown in FIG.

When the object is further moved and the object is partially included or entirely included in the emission range of the IRLED as in the case of FIG. 5, the infrared reflectance is kept constant. In this state, the PD signal value is brought back into the state determination threshold (max, min) and kept constant. This corresponds to b1 in section B. In the case of b1 in the interval B, it is checked whether the PD signal value is kept within the state determination threshold values (max, min) for more than a predetermined state determination time. If it is maintained, it is determined as a constant state, and the constant state frequency is output between the time points t3 and t4.

As the object moves further and starts to go out of the IRLED emission range, the PD signal value is decreased to move out of the status judgment threshold (max, min). That is, in the case of b2 in the section B, the state value changes from the constant state to the change state again. In this variation state, the variation state frequency is generated during the time points t4 and t7 of FIG. Here, since the moving speed of the object is the same as in a1 in the section B, the variation frequency is constant as shown in FIG.

As in a2 in section B, if the object is further moved and completely out of the IRLED emission range, the PD signal value remains constant again and enters the status judgment threshold (max, min). As a result, if the PD signal value is maintained within the state determination threshold (max, min) for more than a constant state determination time, it is determined as a constant state again.

As in the interval C, as the object does not enter the IRLED emission range again, if the PD signal value is maintained within the status determination threshold (max, min) for more than the standby state determination time, the state changes from the constant state to the standby state. In this case a standby frequency is generated.

In Fig. 12, reference numerals Ta, Tb, Tc, and Td denote constant state determination time, standby state determination time, constant state determination time, and standby state determination time, respectively. Also, reference numerals PS and PM indicate PD signal values and immediately preceding section average values, respectively.

FIG. 13 is a diagram exemplarily illustrating a graph approximating a change in another state value and a change in a switching control signal frequency according to FIG. 7.

In the case of FIG. 13, the same as in FIG. 12 except that the moving speed of the object increases instead of the constant velocity.

In the graph shown at the top of the figure, the horizontal axis represents time and the vertical axis represents PD signal values, respectively. On the other hand, in the graph shown at the bottom of the figure, the horizontal axis indicates time and the vertical axis indicates the frequency of the switching control signal, respectively.

Referring to FIG. 13, when the moving speed of an object increases, the frequency increases in proportion to the speed. In addition, even if the moving speed is constant, the change rate of the PD signal value may be increased by the operation characteristics of the PD element and the geometric arrangement of the IRLED and the PD. For example, a change in the PD signal value is detected faster between the time points t2 and t3 of FIG. 13.

If the moving speed of the object is changed from the initial standby state to the fluctuating state at time t1, the minimum frequency, which is the input setting value, is output when the moving speed of the object is lower than the moving speed min.

If the movement speed increases at the time t2 and becomes larger than the movement speed min, a frequency proportional to the movement speed is output to the time t3 as shown in FIG. 11. .

At the time t3, when the movement speed increases gradually and reaches the movement speed max value, the maximum frequency is output. Even if the speed is further increased after time t3, the maximum frequency is output until time t5.

At the time t5, if the movement state changes from the fluctuating state to the constant state, the constant state frequency is output until the time t6.

At the time t6, when the movement state changes from the constant state back to the fluctuating state, the maximum frequency is output because the movement speed is larger than the movement speed max at the beginning of the operation. Since the movement speed is reduced from then on, the frequency is also reduced. If the movement speed is less than the movement speed min at time t9, the minimum frequency is output. Except for the interval graphs VF1 and VF2 in the above-described part, the graph in FIG. 13 shows generating the output frequency in the same manner as in FIG. 12.

On the other hand, in the detailed description of the present invention has been described with respect to specific embodiments, various modifications are possible without departing from the scope of the invention. Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be defined by the equivalents of the claims of the present invention as well as the following claims.

Claims (20)

A motion speed generation unit configured to receive an input signal and generate a motion speed signal of the object;
A previous section average value generator configured to compare the input signals received in the previous sections to generate a previous section average value;
A state value generator configured to generate a motion state value for the input signal based on the average value of the last section and setting values for the determination of the motion state of the object;
A controller configured to apply the set values to the state value generator and to generate the switching control signal frequency value by receiving the movement speed signal and the movement state value; And
And a light emitting diode switching control signal generating unit generating a light emitting diode switching control signal in response to the switching control signal frequency value and applying the light emitting diode switching control signal to a driving unit for driving the light emitting diode.
The apparatus of claim 1, wherein the input signal is one or more photodiode signals.
The method of claim 1, wherein the control unit,
A setting value register unit for storing frequency information, speed information, and time information as setting values for determining the motion state of the object;
A variable state frequency generator for generating a variable state frequency for a moving speed of the object according to the frequency information and the speed information applied from the set value register unit;
A constant state frequency generator for generating a constant state frequency by receiving frequency information related to a constant state from the set value register unit in the constant state frequency generation mode; And
And a multiplexer outputting the variable state frequency or the constant state frequency as the switching control signal frequency value according to the motion state value.
4. The light emitting diode drive control apparatus according to claim 3, wherein the multiplexer further outputs a standby state frequency provided from the set value register section as the switching control signal frequency value according to the motion state value.
The method of claim 3, wherein the state value generating unit,
A state determination threshold generation unit for generating a maximum and a minimum state determination threshold by receiving the average range of previous ranges applied from the previous range average value generation unit and a state determination threshold ratio applied from the control unit in a state determination threshold generation mode; And
And a state determiner configured to determine a movement state of the input signal and generate the movement state value according to the time information and the maximum and minimum state determination thresholds applied from the control unit.
The light emitting diode driving control apparatus of claim 1, further comprising a filter unit for removing noise included in the input signal at a front end of the movement speed generating unit and the previous range average value generating unit.
The light emitting diode driving control apparatus of claim 1, wherein the light emitting diode switching control signal has different on / off periods in a standby state and a motion detection state.
8. The LED driving control device of claim 7, wherein an on / off period in the motion detection state is smaller than an on / off period in the standby state.
The light emitting diode driving control apparatus of claim 8, wherein an on / off period in the motion detection state is varied according to a motion state of the object.
Receiving an input signal to generate a motion velocity signal of the object, and comparing the input signals received in the previous sections to generate an average value of the preceding section;
Generating a motion state value for the input signal according to the average value of the last section and set values for the determination of the motion state of the object;
Generating a switching control signal frequency value using the motion speed signal and the motion state value;
And generating a light emitting diode switching control signal according to the switching control signal frequency value and applying the light emitting diode switching control signal to the light emitting diode driver.
The method of claim 10, wherein the input signal is a signal received through a plurality of photodiodes.
The method of claim 10, further comprising a filtering step of removing noise included in the input signal before generating the motion state value.
The method of claim 10, wherein the light emitting diode switching control signal has a different frequency in a standby state and a motion detection state.
The method of claim 13, wherein a frequency in the motion detection state is higher than a frequency in the standby state.
The method of claim 13, wherein the frequency in the motion detection state is varied according to the motion state of the object.
The method of claim 13, wherein the set values include frequency information, speed information, and time information.
An infrared light emitting diode array unit for irradiating infrared rays to an object;
A photodiode array unit configured to receive the infrared rays reflected from the object and generate a current signal according to the received amount;
A photodiode signal processor for processing the current signal to generate a photodiode signal value represented as digital data;
A motion detection and recognition unit for recognizing the approach or movement direction of the object by using the photodiode signal value:
A light emitting diode driver for driving the infrared light emitting diode array unit in response to an applied switching control signal signal; And
And an infrared light emitting diode controller configured to generate a switching control signal according to the degree of movement of the object using the photodiode signal value.
The method of claim 17, wherein the LED driving unit,
A motion speed generation unit which receives the photodiode signal value as an input signal and generates a motion speed signal of an object;
A previous section average value generator configured to compare the input signals received in the previous sections to generate a previous section average value;
A state value generator configured to generate a motion state value for the input signal based on the average value of the last section and setting values for the determination of the motion state of the object;
A controller configured to apply the set values to the state value generator and generate the switching control signal frequency value by receiving the movement speed signal and the movement state value; And
And a light emitting diode switching control signal generator configured to generate a light emitting diode switching control signal in response to the switching control signal frequency value.
The apparatus of claim 18, wherein a frequency of the light emitting diode switching control signal in the motion detection state of the object is higher than a frequency in the standby state of the object.
The apparatus of claim 19, wherein a frequency of the light emitting diode switching control signal is varied according to a motion state of the object.

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