KR20100106010A - System for measuring tilt and performance of cellular phone's camera - Google Patents

Abstract

PURPOSE: A system for measuring the tilt and performance of a cellular phones camera by using a displacement sensor is provided to improve workability by directly irradiating a laser beam to a bobbin of an actuator without using a real lens or a dummy at the actuator. CONSTITUTION: A displacement sensor(30) senses displacement depending on the motion of an actuator(20) by directly irradiating a laser beam onto the plural positions of the actuator. A controller(40) converts a sensed displacement into an analog signal, and a relay station(50) relays the converted analog signal. A control unit(60) measures the tilt depending on the displacement of the actuator in a preset algorithm by using the relayed signal. The control unit outputs the driving voltage of the actuator.

Description

System for measuring tilt and performance of mobile phone cameras using displacement sensor {SYSTEM FOR MEASURING TILT AND PERFORMANCE OF CELLULAR PHONE'S CAMERA}

The present invention relates to a tilt and performance measurement system of a mobile phone camera using a displacement sensor.

Recently, mobile phones have been widely used to perform functions such as taking pictures, recording music, receiving DMB broadcasts as well as transmitting voices and texts with the other party.

As described above, the camera module which performs the photo shooting function of the mobile phone which performs various functions is a bobbin in which a coil focusing on the subject while moving back and forth combined with the incident lens and the lens receives the reflected light of the subject and an electromagnetic force outside the bobbin. It consists of a housing equipped with a magnet for advancing the bobbin and an actuator including a printed circuit board. It is designed to focus on the camera.

However, the camera module of the mobile phone often causes changes in driving performance characteristics due to assembly defects, component defects, and other factors.

In particular, when there is a change in the actuator driving performance characteristics of the camera module, the bobbin of the actuator is not taken at the exact distance (point) from the subject, but the shot is taken out of the shooting point, resulting in a defect in resolution. There is a problem.

Thus, the assembled actuator measures the driving performance characteristics. Among these, in order to measure the tilt (tilt) of the actuator, the light is reflected by irradiating laser light, and the distance difference is measured and converted into an angle to calculate the tilt. It was. In particular, the amount of tilt during driving of the actuator is represented by continuously expressing the amount of tilt for voltage, current, and displacement in order to calculate dynamic tilt.

Conventionally, in order to calculate such a tilt value, the actuator has to mount a reflector on a dummy lens or a real lens.

However, according to this conventional structure, the following problems arise.

First, a difference in the measured value occurs according to the flatness of the reflector provided on the dummy lens or the real lens and the kind of the reflector, and a difference in the measured value occurs according to the degree of wear of the reflector.

In addition, a dummy lens or a real lens should be assembled to the bobbin. In the case of the dummy lens, the flatness of the bobbin should be secured, and the measurement value will be accurate. Exhausted,

Accordingly, an object of the present invention is to provide a tilt and performance measurement system of a mobile phone camera using a displacement sensor that is excellent in workability and improves the accuracy of measurement data.

The above object is an actuator mounted on a jig; A displacement sensor that detects displacement caused by movement of the actuator by irradiating laser light to a plurality of positions of the actuator; A controller for converting the displacement detected by the displacement sensor into an analog signal; A repeater for relaying the analog signal converted by the controller; And a controller which receives the signal relayed by the repeater and measures the tilt according to the displacement of the actuator with a predetermined algorithm and outputs a driving voltage of the actuator, wherein the controller is configured to perform the algorithm based on the received displacement. It is achieved by a tilt and performance measurement system of a mobile phone camera using a displacement sensor that constructs a virtual plane using the and measures the tilt value using the angle between these planes.

According to the above arrangement, since the laser light is irradiated directly to the bobbin of the actuator without using a dummy or a real lens, the workability is excellent and the accuracy of the measurement data is improved.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a tilt and performance measurement system according to an embodiment of the present invention.

Referring to FIG. 1, the tilt and performance measurement system of the present invention includes a jig 10, an actuator 20, a displacement sensor 30, a controller 40, a repeater 50, a computer 60, and an amplifier 70. ).

The jig 10 is configured to mount and fix the actuator 20 to be measured, and to fix the actuator 20 to X, Y, and Z-axis stages.

The actuator 20 is a driving unit of the camera module and drives back and forth to focus on a subject to be photographed. According to the present invention, the actuator 20 is not equipped with a dummy lens or a real lens unlike the prior art, and as will be described later, the laser light irradiated from the displacement sensor 30 installed on the upper portion of the actuator 20 directly from the bobbin. Reflect.

As described above, the displacement sensor 30 is a pair of three or more (31, 32, 33), and emits a laser light to the actuator 20 itself fixed to the jig 10, the actuator 20 The displacement of the laser light is detected by the movement (displacement) of the laser beam. Each displacement sensor 31, 32, 33 comprises a laser light emitting portion and a light receiving portion.

The controller 40 converts the laser light signal detected and input from the displacement sensor 30 into an electrical analog signal, and outputs the converted analog signal. For example, the controller 40 includes an encoder.

The repeater 50 relays an analog signal output from the controller 40 and, for example, relays a signal input through a BNC cable to each output terminal.

The computer 60 includes a conventional desktop or notebook computer that calculates, compares, and judges an input signal, and displays the determined state on a monitor, and collects data inside the computer 60 to collect data. Device (DAQ) 62 and any algorithms needed for the measurement.

The amplifier 70 amplifies the driving voltage output from the data collection device 62 of the computer 60 to a voltage (or current) of a magnitude that the actuator 20 can drive, and the amplified voltage (or current) is It is supplied to the actuator 20 and is input to the data collection device 62 of the computer 60. If the output voltage and output current of the data acquisition device are large, the amplifier may not be used.

According to the configuration as described above, X in accordance with the tilt specification of the actuator 20 to be measured through the input unit of the computer 60, while the actuator 20 is fixed to the X, Y, and Z axis of the jig 10 In this case, the minimum and maximum tilt values of the Y axis and the tilt range or the position of the tilt to be measured are entered.

Subsequently, when the measurement is started through the input of the computer 60, the data collection device 62 of the computer 60 outputs a driving voltage to the amplifier 70, and the amplifier 70 drives the actuator 20. The amplified voltage (or current) is input to the data collection device 62 of the computer 60 at the same time as the amplified voltage (or current). In this case, the input voltage may be input as a triangular wave or other step waves or sine waves.

The actuator 20 starts to move (move) by the input driving voltage, and as shown in FIG. 2, the displacement sensors 31, 32, and 33 are placed on the bobbin 21 of the actuator 20. The laser beam is directly irradiated to the set positions a, b, and c, and the actuator 20 receives the reflected optical signal according to the movement from the minimum point to the maximum point, converts it into an analog signal through the controller 40, and then repeats the repeater. Input to the data collection device 62 of the computer 60 through 50. Subsequently, the data collection device 62 of the computer 60 collects the X and Y axis tilt displacement due to the DC voltage according to the movement of the actuator 20 to form a graph shown in FIG. 3.

Specifically, as described above, when receiving the reflected optical signal measured according to the movement of the actuator 20 from the displacement sensor 30, the computer 60 uses a predetermined algorithm provided in FIG. Construct a virtual reference circle Cref represented by a solid line. At this time, the virtual line passing through the center point of the virtual reference circle is set to a reference line having a tilt value of 0 (that is, input current i = 0 mA).

Subsequently, while driving the actuator 20 to move from the minimum point to the maximum point, each displacement sensor 31, 32, 33 irradiates a laser light to the same position (a, b, c) to receive the reflected light signal, At this time, when the tilt occurs, an inclined imaginary circle Ctilt is formed as shown by a dotted line in FIG. 3. The imaginary line passing through the center point of this imaginary circle is eventually inclined at an angle of θ relative to the baseline, so the tilt value is

Becomes

Although the imaginary circle has been described here, a imaginary plane composed of coordinate values of X and Y in a broad sense is sufficient.

On the other hand, using the displacement sensor value at any one of the three positions (a, b, c) and the tilt value calculated above, the current (voltage) versus tilt, displacement versus tilt, and X tilt versus Y tilt waveforms are obtained. You can print

Here, the current (voltage) vs. tilt can confirm the tilt at a specific current (voltage) and is represented by a waveform as shown in FIG.

In addition, the displacement vs. tilt can confirm the tilt at a specific displacement, so that the resolution in the camera module can be inferred by checking the tilt at the macro or infinity. Displacement versus tilt is represented by a waveform as shown in FIG.

In addition, X tilt vs. Y tilt can determine which axis the actuator is tilted, and as a result, it can be inferred which resolution falls in the camera module, which is represented by a waveform as shown in FIG. 6.

In addition, the current (voltage) versus displacement can measure the performance of a typical actuator, i.e. starting current, sensitivity, operating distance and hysteresis, and shows a waveform as shown in FIG.

As described above, according to the present invention, since the laser light is directly irradiated to the bobbin of the actuator without using a dummy or a real lens, the workability is excellent and the accuracy of the measurement data is improved.

In the above description, the embodiment of the present invention has been described, but various changes can be made at the level of those skilled in the art. For example, the computer may be configured as a control unit that performs the same function, and the whole computer may be configured as a single measuring device.

Therefore, the scope of the present invention should not be construed as being limited to the above embodiment, but should be interpreted by the claims described below.

1 is a block diagram of a tilt and performance measurement system according to an embodiment of the present invention.

Figure 2 shows the position of the laser light irradiated to the actuator applied to the present invention.

3 shows an imaginary circle composed of displacement sensor values on a coordinate axis.

4 to 6 show waveforms by the displacement sensor value and the tilt value, respectively, FIG. 4 shows current (voltage) vs. tilt, FIG. 5 shows displacement vs. tilt, FIG. 6 shows X tilt vs. Y tilt, and FIG. 7 shows current (voltage). ) Vs. displacement waveform.

Claims (7)

An actuator mounted on the jig; A displacement sensor that detects displacement caused by movement of the actuator by irradiating laser light to a plurality of positions of the actuator; A controller for converting the displacement detected by the displacement sensor into an analog signal; A repeater for relaying the analog signal converted by the controller; And Receiving a signal relayed from the repeater and measuring the tilt according to the displacement of the actuator by a predetermined algorithm and includes a control unit for outputting the drive voltage of the actuator, The control unit is a tilt and performance measurement system of a mobile phone camera using a displacement sensor to configure a virtual plane using the algorithm based on the received displacement and to measure the tilt value using the angle between the plane. The method of claim 1, The displacement sensor is a tilt and performance measurement system of a mobile phone camera using a displacement sensor consisting of three or more pairs. The method of claim 2, The displacement sensor is a tilt and performance measurement system of a mobile phone camera using a displacement sensor including a light emitting unit for emitting a laser light, and a light receiving unit for collecting the reflected laser light. The method of claim 1, Laser light from the displacement sensor is a tilt and performance measurement system of a mobile phone camera using a displacement sensor that is directly irradiated to the bobbin of the actuator. The method of claim 1, The tilt value is a tilt and performance measurement system of a mobile phone camera using a displacement sensor is a tangent component of the angle between the angle. The method of claim 1, A mobile phone camera using a displacement sensor that outputs a current (voltage) versus tilt, displacement versus tilt, or X tilt versus Y tilt waveform using a displacement sensor value at any one of the plurality of positions and the measured tilt value. Tilt and performance measurement system. The method of claim 1, The control unit is a tilt and performance measurement system of a mobile phone camera using a displacement sensor consisting of a computer device having a data collection device for collecting data therein.

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