CN201141943Y - Micro-electromechanical scanning controller for generating time sequence frequency - Google Patents

Abstract

The utility model relates to a produce time sequence frequency's micro-electromechanical scanning controller, the controller of the micro-electromechanical oscillating speculum of being used in two-way laser scanning device, it is the resonance frequency of can listening micro-electromechanical speculum, in order to send the frequency modulation signal and the amplitude modulation signal of micro-electromechanical speculum, make the bridge circuit adjustment of micro-electromechanical speculum stable, and can send out and correspond and produce a time sequence signal (CLK signal) at the resonance frequency of micro-electromechanical speculum at that time, so that scan data (data string) can be sent out in the effective scanning window (scanning window) of forward (forward) and reverse (reverse direction) scanning, reach the scanning effect of high accuracy.

Description

MEMS scan controller for timing frequency generation

technical field

The utility model relates to a micro-electro-mechanical scanning controller (MEMS scan controller with clock frequency) for generating timing frequency, especially a micro-electro-mechanical reflection device used in a bi-direction laser scanning unit (bi-direction laser scanning unit, referred to as bi-directional LSU). The controller of the micro-electric-mechanical mirror (MEMS mirror for short) generates a timing frequency signal so that the laser light source can transmit the laser light within the effective scanning window according to the timing frequency.

Background technique

At present, most laser scanning units (LSU) use a rotating polygon mirror (Polygon Mirror) to rotate and control the scanning of laser light at high speed. However, since the rotating polygon mirror is driven by hydraulic pressure, its speed limit, high price, and noise Factors such as large size and slow startup have gradually failed to meet the requirements of high speed and high precision. In recent years, micro-electronic-mechanical system oscillatory mirrors (MEMS mirrors) with torsion oscillators have begun to develop, and will be used in imaging systems, scanners ( scanner) or laser printer (laser scanning unit, referred to as LSU), its scanning efficiency (Scanning efficiency) will be higher than the traditional rotating polygonal mirror.

The micro-electromechanical mirror (MEMS mirror) in the laser scanning unit (LSU) is composed of a control board with a bridge circuit, a torque oscillator and a mirror surface, and the mirror surface is moved back and forth in the left and right directions of the axis through the resonant magnetic field. Swing; when the laser light hits the mirror surface of the MEMS mirror, the mirror surface changes the rotation angle with time, so that the laser light incident on the mirror surface of the MEMS mirror is reflected to the central axis of the MEMS mirror in various ways. angle to scan. Because the micro-electromechanical mirror can ignore the influence of light wavelength and achieve high resolution and large rotation angle, it is widely used in commercial, scientific and industrial applications, such as US5,408,352, US5,867,297, US6,947,189 , US7,190,499, TW M253133, JP 2006-201350, etc. Since the micro-electromechanical mirror swings back and forth in the left and right directions on the axis, it can be developed into bi-directional scanning to improve scanning efficiency, and constitute a bi-directional laser scanning unit (bi-direction laser scanning unit), but this also increases the difficulty of control.

Since the MEMS mirror swings back and forth in a resonant manner, the angle and stability of its swing will affect the accuracy of the laser scanning device. On the controller of the two-way laser scanning device of the MEMS mirror, the existing technology focuses on the micro-electromechanical mirror. Stable control of the electromechanical mirror, such as adjusting the resonant frequency of the MEMS mirror, adjusting the working angle of the MEMS mirror, or using a voltage controlled oscillator (VCO) to adjust the frequency. The magnetic conduction technology of the medium or the use of voltage to change the capacitance to achieve the purpose of changing the frequency, such as US patents US2006/00139113, US2005/0139678, US2007/0041068, US2004/0119002, US7,304,411, US5,121,138; Japanese patent JP63-314965 wait. However, the two-way laser scanning device, taking the accuracy of 600DPI (dot per inch) of A4 size as an example, must send out 5102 light spots (light spots) of laser light when scanning in each direction, so that these 5102 light spots can be used effectively. The scanning window (imaging interval) is completely emitted, and the effective scanning window will not move due to the frequency variation or amplitude variation of the micro-electromechanical mirror, so that the 5102 light spots will be shifted and cannot be completely imaged on the target object. Therefore, it is one of the main control points to calculate the frequency of the MEMS mirror to give the correct signal to the laser controller that emits the laser light. U.S. Patent US2006/0279364 discloses the use of the resonant mode of the micro-electromechanical mirror, which is controlled by a timing counter using a reference table; U.S. Patent No. 6,891,572 discloses the use of a phase-locked circuit to control the synchronous storage of scanning signals into memory; It discloses using a photoelectric sensor to control the swing stability of the micro-electromechanical mirror; US Patent No. 6,870,560 and US No. 6,987,595 disclose using a counting controller or dynamically adjusting the resonance frequency to control the rotation of the photosensitive drum (drum) and the frequency of the laser scanning light. However, for bi-directional scanning, it is necessary to develop a fast and effective control method and controller so that the scanning light can completely form an image on the target object without deviation in the effective scanning window.

The utility model discloses a control method capable of generating timing signals and a micro-electromechanical scanning controller formed by such a method. In addition to sending out frequency modulation signals and amplitude modulation signals of micro-electromechanical mirrors, the bridge type of micro-electromechanical mirrors The circuit is adjusted stably, and can send a timing signal corresponding to the resonant frequency of the micro-electromechanical mirror at that time, which is provided to the laser controller through this timing signal, so that the laser light can emit scanning light in the effective scanning window to achieve high-precision scanning Effect.

Contents of the invention

The main purpose of the utility model is to provide a micro-electro-mechanical scanning controller used in a bi-directional scanning micro-electro-mechanical laser scanning device to overcome the above-mentioned defects.

In order to achieve the above object, the technical solution adopted by the utility model is to provide a micro-electromechanical scanning controller for generating timing frequency, which is applied to a laser scanning device, and the laser scanning device includes a laser light source for generating laser Light, a micro-electromechanical mirror, which uses resonance to drive the mirror to scan the laser light on the target object in forward scanning and reverse scanning, a photoelectric sensor that receives the scanning light and converts the light into a photoelectric sensing signal, a control The bridge circuit of the micro-electromechanical mirror and a laser controller control the laser light source to emit the laser light source; it is characterized in that:

The MEMS scanning controller is used to detect the resonant frequency of the MEMS mirror and generate a timing signal to drive the laser controller to emit a laser light source and scan through the MEMS mirror, including a logic unit, at least one D-type Flip-flop, a phase-locked circuit and a counting comparator, wherein:

The logic unit receives the photoelectric sensing signal generated by the photoelectric sensor, and calculates the interval time between each photoelectric sensing signal to generate the frequency modulation signal of the micro-electromechanical mirror, The amplitude modulation signal and the stabilized signal of the MEMS mirror;

The D-type flip-flop receives the frequency modulation signal and the amplitude modulation signal generated by the logic unit and generates a resonance frequency signal and a feedback signal;

The phase-locked circuit receives the resonant frequency signal generated by the D-type flip-flop and generates a timing signal;

The counting comparator receives the timing signal, accumulates the pulses of the timing signal to a certain number and generates a braking signal, and clears the accumulated timing signal, and the braking signal generates the next one via the D-type flip-flop Feedback signal; when the laser light source receives the timing signal sent by the micro-electromechanical scanning controller, the laser controller sends the scanning data within the effective scanning window according to the timing signal.

Secondly, a micro-electro-mechanical scanning controller for generating timing frequency is provided, which is applied to a laser scanning device. The laser scanning device includes a laser light source for generating laser light, and a micro-electro-mechanical mirror using a resonance method. Drive the mirror to scan the laser light on the target in forward scanning and reverse scanning. At least two photoelectric sensors receive the scanning light and convert the light into a photoelectric sensing signal. A bridge circuit that controls the micro-electromechanical mirror and a laser controller which controls the laser light source to emit a laser light source; it is characterized in that:

The MEMS scanning controller is used to detect the resonant frequency of the MEMS mirror and generate a timing signal to drive the laser controller to emit a laser light source and scan through the MEMS mirror, including a logic unit, at least one D-type Flip-flop, a phase-locked circuit and a counting comparator, wherein:

The logic unit receives photoelectric sensing signals generated by at least two photoelectric sensors, and calculates the interval time between each photoelectric sensing sensing signal to generate the frequency modulation signal of the micro-electromechanical mirror, The amplitude modulation signal and the stabilized signal of the MEMS mirror;

The D-type flip-flop receives the frequency modulation signal and the amplitude modulation signal generated by the logic unit and generates a resonance frequency signal and a feedback signal;

The phase-locked circuit receives the resonant frequency signal generated by the D-type flip-flop and generates a timing signal;

The counting comparator receives the timing signal, accumulates the pulses of the timing signal to a certain number and generates a braking signal, and clears the accumulated timing signal, and the braking signal generates the next one via the D-type flip-flop Feedback signal; when the laser light source receives the timing signal sent by the MEMS scanning controller, the laser controller sends the scanning data within the effective scanning window according to the timing signal.

Compared with the prior art, the utility model has the beneficial effect that it is used to detect the vibration frequency and amplitude of the micro-electromechanical mirror, and to generate a signal to the laser controller and the bridge circuit for controlling the micro-electromechanical mirror. Adjust the vibration frequency and amplitude of the MEMS mirror, and stabilize the vibration of the MEMS mirror, so that the laser light can be scanned correctly in the effective scanning area;

When the frequency f _CLK (t) of the timing signal is sent out by the MEMS scan controller, a data brake signal is sent to drive the laser controller to start sending the scan data, so that the scan data is still transmitted accurately.

Description of drawings

Fig. 1 is a schematic diagram of a bidirectional laser scanning device of the present invention;

Fig. 2 is the relationship diagram between the angle and time of the micro-electromechanical reflector reflecting laser light of the utility model and the relationship between the photoelectric sensor and the time when the photoelectric sensor sends out the photoelectric detection signal;

Fig. 3 is the microelectromechanical scanning controller schematic diagram of the present utility model;

Fig. 4 is a relation diagram of photoelectric sensing signal, scanning light angle, scanning data and time of the utility model;

Fig. 5 is the relationship diagram of the first modulation signal sent by the micro-electromechanical scanning controller of the utility model after receiving the laser controller signal and the photoelectric sensor signal;

Fig. 6 is a relationship diagram of the first modulation signal, the second modulation signal and the third modulation signal of the present invention;

Fig. 7 is the relationship diagram of the resonance frequency signal of the utility model;

Fig. 8 is a relation diagram of the photoelectric sensing signal of the utility model;

Fig. 9 is a relation diagram of each signal of the utility model;

Fig. 10 is a control flow chart of the micro-electro-mechanical scanning controller of the utility model;

Fig. 11 is a flowchart of scanning data control of the utility model;

Fig. 12 is a schematic diagram of the MEMS scanning controller of the second embodiment of the present invention;

Fig. 13 is a schematic diagram of the MEMS scanning controller of the third embodiment of the present invention;

Fig. 14 is a schematic diagram of the MEMS scanning controller of the fourth embodiment of the present invention;

Fig. 15 is a schematic diagram of the MEMS scanning controller of the fifth embodiment of the present invention;

Fig. 16 is a relationship diagram of two photoelectric sensing signals in the fifth embodiment of the present invention.

Explanation of reference numerals: 10-MEMS mirror; 11-laser light source (pre-scanlaser); 13-scanning lens (post-scan lens); 14a, 14b-photoelectric sensor (PD detector); 15- Target drum; 21-MEMS scan controller; 22-bridge circuit (Bridge circuit); 23-laser controller; 111-laser light (Laserlight); 113( a, b, c), 114, 115 (a, b) - scanning light (Scanning light); 211 - logic unit (Control logic); 212-D type positive and negative device I (D inverter I); 213-D type Flip-flop II (D inverterII); 214-phase locked loop PLL; 215-counter comparator (Counter compare); 216-RF delay circuit (RF delay circuit); 217-data-driven delay circuit (data trigger delay circuit); 310-timing signal (CLK signal); 311-driving signal (driving signal); 312a, 312b-photoelectric sensing signal (PD signal); 313-start enabling signal (ENB signal); 314- Adjust signal (Adjust signal); 315-stable signal (Stable signal); 316a-first modulation signal (PWM1 signal); 316b-second modulation signal (PWM2 signal); 316c-third modulation signal (PWM3 signal); 317a, 317b, 317c-data trigger signal (Data trigger signal); 318-scanning data (Data string); 321-resonant frequency signal (Resonant frequency signal); 322-braking signal (Trigger signal); 323-oscillating signal (Q signal).

Detailed ways

The above-mentioned and other technical features and advantages of the present invention will be described in more detail below in conjunction with the accompanying drawings.

<Example 1>: A MEMS laser scanning device of a photoelectric sensor

This embodiment is applied to a micro-electromechanical laser scanning device of a photoelectric sensor; as shown in Figure 1, for the micro-electromechanical laser scanning device, the laser light source 11 in the device is controlled by the laser controller 23, when the laser controller 23 sends scanning data 318 , then the laser light 111 is generated via the laser light source 11; the laser light 111 shoots to the mirror surface of the micro-electromechanical mirror 10, and the micro-electromechanical mirror 10 makes the mirror vibrate in the forward and reverse directions with the resonant frequency f; the present embodiment uses the frequency f =2500±(2500*5%)HZ, the micro-electromechanical mirror 10 with a maximum scanning angle of ±23°; the laser light 111 scans at an angle of θ _c =±23*2° to become the right edge scanning light 115a to the left The edge scanning light 115b; the scanning light in the 2θ _n range is formed by 113a to 113b, which is the effective scanning window, and the present embodiment is set at θ _n =±19*2°; and in the present embodiment, the photoelectric sensor 14a is set At an angle of θ _p =±21*2°, the scanning light 114 a is detected by the photoelectric sensor 14 a. The photoelectric sensor 14a can receive the scanning light 114a and convert the light into an electrical trigger signal. The scanning light rays 113 a to 113 b pass through the rear scanning lens 13 and form images on the target object 15 such as a photosensitive drum. In order to maintain the stability of the 2θ _c angle, the MEMS reflector 10 is controlled by the bridge circuit 22, and the bridge circuit 22 can send a driving signal 311 to make the MEMS reflector 10 swing. When the MEMS reflector 10 swings too much , the bridge circuit 22 can be controlled to send a drive signal 311. Similarly, when the MEMS mirror 10 swings too small, the bridge circuit 22 can be controlled to send a drive signal 311. The bridge circuit 22 is based on the micro-electro-mechanical scanning control Controlled by the first modulation signal 316a, the second modulation signal 316b and the third modulation signal 316c output by the controller 21. In addition, the laser controller 23 is the main console of a laser printer or a multifunctional business machine, and is used to send scan data 318 to control the laser light source 11, send a start enabling signal 313 for starting the microelectromechanical mirror 10, and send an adjustment microelectromechanical The adjustment signal 314 of the mirror 10 is used to determine whether the MEMS mirror 10 is stable, whether it can send out the scanning data 318 , and at what frequency to send out the scanning data 318 .

The micro-electromechanical scanning controller 21 receives the start enable signal 313 of the laser controller 23, receives the adjustment signal 314 of the laser controller 23, generates a first modulation signal 316a for frequency modulation, and generates a second modulation signal for frequency modulation 316b and the third modulation signal 316c that generates amplitude modulation, and the stable signal 315 that generates the stable MEMS mirror 10, and detects the resonance of the MEMS mirror 10 by receiving the photoelectric sensing signal 312a sent by the photoelectric sensor 14a Frequency and generate a timing signal 310 to provide to the laser controller 23 to drive the laser light source 11 in a timely manner, so that the image signal sent by the laser light source 11 is calculated and phased by the micro-electromechanical scanning controller 21, so that the timing signal 310 is the correct timing frequency , the scanning light beams 113 a to 113 b scanned by the laser light beam 111 are located in the effective scanning window, even if the scanning light beams 113 a to 113 b generate nβ light spots on the target object 15 .

The MEMS scan controller 21 includes a logic unit 211, a D-type flip-flop I 212, a D-type flip-flop II 213, a phase-lock circuit 214 and a counting comparator 215. The logic unit 211 can receive the trigger photoelectric sensing signal 312a generated by the photoelectric sensor 14a, and calculate the photoelectric sensing signal 312a generated by the photoelectric sensor 14a each time, so as to generate the frequency modulation signal and the amplitude modulation signal of the micro-electromechanical mirror 10. Modulation signal, the first modulation signal 316a, the second modulation signal 316b and the third modulation signal 316c of the amplitude; the phase lock circuit 214 can generate the timing signal 310, when the laser controller 23 receives the microelectromechanical scanning controller 21 The timing signal 310 sent by the phase-locking circuit 214 can send the scanning data 318 according to the frequency of the timing signal 310, as follows:

As shown in Figure 2, the micro-electromechanical mirror 10 vibrates left and right along the Y axis along the X axis, and its left and right vibrations are ± _θc . At any time t, the angle between the scanning light reflected after the incident laser light 111 and the central optical axis (113c) θ(t) presents a sinusoidal waveform over time, and when the reflected scanning light reaches the photoelectric sensor 14a, the photoelectric sensing signal 312a triggered for the first time is generated, when the microelectromechanical mirror 10 vibrates to the right to the maximum angle _θc , the θ(t) angle is the largest; thereafter, the micro-electromechanical mirror 10 starts to resonate, the θ(t) angle decreases, and when the reflected scanning light reaches the photoelectric sensor 14a, a second triggered photoelectric sensing signal 312a is generated , when the scanning light reaches the effective scanning window (113a to 113b, that is, between points a and b in Figure 2), the relationship between the angle θ(t) and time t is the closest to a straight line, which is the effective forward scanning scanning window; when the microelectromechanical mirror 10 vibrates to the left to the maximum angle -θ _c , the θ(t) angle is the largest; thereafter, the microelectromechanical mirror 10 starts to resonate, and the θ(t) angle decreases, when scanning The light reaches the effective scanning window (113b to 113a, i.e. between points b' and a' in Figure 2), which is the effective scanning window for reverse scanning. When the MEMS mirror 10 continues to vibrate to the right, the scanning light reaches the photoelectric When the sensor 14a, the photoelectric sensing signal 312a triggered for the third time is generated, and the scanning of a cycle ± θ _c is completed. When the micro-electromechanical mirror 10 reaches the maximum angle θ _c , it starts to resonate, and the angle of θ (t) decreases, and the scanning When the light reaches the photoelectric sensor 14a, a fourth triggered photoelectric sensing signal 312a is generated.

As shown in Figure 3, the MEMS scan controller 21 of the present embodiment is made up of a logic unit 211, two D-type flip-flops 212/213, a phase-lock circuit 214 and a counting comparator 215; the MEMS scan controller 21 accepts The photoelectric sensing signal 312a sent by the photoelectric sensor 14a, since the micro-electromechanical mirror 10 vibrates back and forth at f frequency, the time to complete a cycle from left to right is T(t), which is called the scanning cycle forward scanning and reverse scanning. As shown in Figure 4, in the scanning period, when θ(t) decreases from the position of the scanning light 114a, it is delayed by _T1 time, and the relationship between angle θ(t) and time t is the closest to the straight line , the laser controller 23 sends out scan data 318, and the time to send the data is T ₂ , which is the effective scan window for forward scanning; after a delay of T ₃ , the laser controller 23 sends out the scan data 318, and the time to send the data is T ₄ , which is the effective scanning window for negative scanning; and T ₁ , T ₂ , T ₃ , and T ₄ are completed within one scanning period T(t). The relationship among T ₁ , T ₂ , T ₃ , and T ₄ is as follows: when f=2500HZ, T ₁ = 1.137×10 ^-5 , T ₂ = T ₄ calculated from Eq.(1)～Eq.(4) =1.2377×10 ^-4 , T ₃ =7.623×10 ^-5 .

When the laser controller 23 sends the start enabling signal 313 to a high potential, the start enable of the microelectromechanical mirror 10 is not issued, and the start enable of the microelectromechanical reflector 10 is sent from a high potential to a low potential. , as shown in Figure 5, but at this time the micro-electromechanical mirror 10 is still unstable after starting. At this time, the laser controller 23 sends a stable signal 315 as a low potential, and sends an adjustment signal 314 as a low potential. After a period of time, the micro-electromechanical mirror 10 stabilized, the stabilization signal 315 turns to a high potential, the adjustment signal 314 turns to a high potential, and sends out a first modulating signal 316a, which becomes a driving signal 311 via a bridge circuit 22, so that the microelectromechanical mirror 10 vibrates to the left; the microelectromechanical After the mirror 10 vibrates back and forth, each scanning period T(t) will trigger the secondary photoelectric sensor 14a, so the logic unit 211 can calculate the triggering period T(t) of the photoelectric sensing signal 312a. When controlling T ₁ , T ₂ , T ₃ , and T ₄ , the logic unit 211 of the MEMS scan controller 21 can receive the trigger signal 312a generated by the photoelectric sensor 14a, and calculate the trigger signal 312a generated by the photoelectric sensor 14a each time, and Generate the first modulation signal 316a, the second modulation signal 316b, and the third modulation signal 316c of the frequency of the MEMS mirror 10; the first modulation signal 316a, the second modulation signal 316b, and the third modulation signal of the amplitude After the modulation signal 316 c is sent out, it is received by the bridge circuit 22 to adjust the vibration frequency and amplitude of the MEMS mirror 10 .

As shown in Figure 6, the pulse relationship between the first modulation signal 316a, the second modulation signal 316b and the third amplitude modulation signal 316c is set as follows: in the resonance period T, the first modulation signal 316a and the second The pulse time of the modulation signal 316b is TA ₁ and TA ₃ , and it is assumed that TA ₁ =TA ₃ , the time interval between the pulses of the first modulation signal 316a and the second modulation signal 316b is TA ₂ and TA ₄ , and it is assumed that TA ₂ =TA ₄ , TA ₁ /TA ₄ , TA ₁ +TA ₂ +TA ₃ +TA ₄ =T, that is, the first modulation signal 316a and the second modulation signal 316b are completed once each within the resonance period T, even if the first The modulation signal 316a and the second modulation signal 316b drive the MEMS mirror 10 so that the resonant frequency of the MEMS mirror 10 is 1/T, wherein the ratio of TA ₁ /TA ₄ is not limited, and can be changed depending on the control loop. In this embodiment, TA ₁ /TA ₄ =1/4 is used; the third modulation signal 316c is the process of dropping from a high potential to a low potential, through the ratio of the time TA ₁₀ for maintaining the high potential to the time TA ₉ for maintaining the low potential Then it is the load D of amplitude adjustment, and the frequency of the third modulation signal 316c is set to 1K (the frequency is not limited, in this embodiment, the frequency of 1K is used), that is, set TA ₁₁ =1/1000, D=TA ₁₀ /TA ₁₁ , TA ₉ +TA ₁₀ =TA ₁₁ , the waveform of the third modulation signal 316c can be adjusted by adjusting the value of D, so as to change the amplitude of the MEMS mirror 10 via the bridge circuit 22 . After the micro-electromechanical mirror 10 reflects the laser light 111, it swings from the left to the right to trigger the photoelectric sensor 14a for the second time, as shown in Figure 8, the time for the adjacent second triggering of the photoelectric sensor 14a is TA ₆ , and the cycle T The ratio of (t) is TA ₆ /(T(t)/2), because the period T(t) changes with time, the ratio TA ₆ /(T(t)/2) also changes with time; for a fixed photoelectric The position of the sensor 14a triggers the scanning light 114a of the photoelectric sensor 14a and the central axis to form an included angle of θ _p , and the maximum scanning angle of the micro-electromechanical mirror 10 is θ _c , that is, when the period is T, R=TA ₆ /(T (t)/2), or the change of the period T can also be calculated by calculating the change of the ratio R, the calculation method is as follows:

$R=\frac{{\mathrm{<figure-callout\; id="6"\; label="TA"\; filenames="Y20082000181400191.png,Y20082000181400213.png"\; state="\{\{state\}\}">TA</figure-callout>}}_6}{\frac{1}{2}T}=\frac{1}{2\mathrm{\&pi;}}\left(2{\sin }^{-1}\left(\frac{{\mathrm{\&theta;}}_p}{{\mathrm{\&theta;}}_c}\right)\right)$ (5)

Since the microelectromechanical mirror 10 uses electromagnetic force or spring force to generate oscillation, at any time t, its resonance frequency is f(t) and its amplitude is A(t), which is not a fixed value, and its lower limit is the lower limit resonance Frequency f _L , its upper limit is the upper limit resonance frequency f _H , that is, f _L ≤ f(t) ≤ f _H ; in this embodiment, f _L =2375, f _H =2625; The environment or its structure influence, the resonant frequency is that f(t) changes will affect the timing when the laser light source 11 sends the scanning data, the amplitude is A(t) changes will affect the reflection angle θ(t), and then affect the scanning light 113a, scanning light The effective scanning window constituted by 113b. Therefore, the method for the MEMS scan controller 21 to control the resonant frequency f(t) and the amplitude A(t) of the MEMS mirror 10 is shown in FIG. 10 and includes the following steps:

S1: Set the initial value of the load (this embodiment sets D=90%), set the initial value T of the cycle (this embodiment sets T=1/fL=4.21×10 ^-4 sec), laser controller 23 Control the laser light source 11 to emit laser light 111;

S2: Check whether the photoelectric sensing signal 312a is triggered twice within a half period of 4.21×10 ^-4 sec;

S3: adjust the frequency by setting the first modulation signal 316a, the second modulation signal 316b and the third modulation signal 316c to a low potential;

S4: Check whether the trigger time ratio of the photoelectric sensing signal 312a, TA ₆ /(T(t)/2), is within R±5%; if TA ₆ /(T(t)/2) is correct, then judge whether Continuously stable, if continuously stable, the laser controller 23 sends a stable signal 315; if TA ₆ /(T(t)/2) is incorrect, then start to adjust the amplitude;

S5: To adjust the amplitude, first judge that TA ₆ /(T(t)/2) is lower than the upper limit 5% or the lower limit 5%;

S6: When adjusting the amplitude, adjust the load D value to increase or decrease the D value to change the amplitude so that the amplitude can trigger the secondary photoelectric sensor 14a within half a cycle;

S7: Fine-tune the frequency after the amplitude is correct, but the frequency cannot exceed f _H .

In this embodiment, the photoelectric sensor 14a is installed at θ _p =21°, that is, when f=2500HZ, from Eq. (5), it can be calculated that R=0.26745. In the method in which the laser controller 23 controls the resonant frequency f(t) and the amplitude A(t) of the MEMS mirror 10, when checking the trigger time ratio of the photoelectric sensing signal 312a, TA ₆ /(T(t)/2 ), that is, the judgment is controlled by R=0.25408～0.28082.

When the frequency T(t) and amplitude A(t) of the MEMS mirror 10 are correct, the laser controller 23 sends a stabilization signal 315 , and then the scanning data 318 can be transmitted. The MEMS scanning controller 21 further includes one or more D-type flip-flops I 212 and D-type flip-flops II 213, which can be generated by the logic unit 211. The frequency modulation signal, the first modulation signal 316a and the second modulation signal 316b, and generate a resonance frequency signal 321 and a feedback signal, or receive the braking signal 322 output by the counting comparator 215, and generate an internal oscillation signal 323 and a feedback signal signal; among them, the low potential time T ₁₂ and high potential time T ₁₃ of the resonant frequency signal 321, as shown in Figure 9; the phase-lock circuit 214 can receive the resonant frequency signal 321 and/or the internal oscillation signal 323 generated by the D-type flip-flop Feedback signal and generate timing signal 310, timing signal 310 is determined by the ratio of T ₁₂ /T ₁₃ of resonance frequency signal 321, that is, nβ pulse is generated in one cycle time; counting comparator 215 can accept phase-locking circuit 214 Timing signal 310, the timing signal 310 is a pulse signal with f(t) multiple frequency; the counting comparator 215 can accumulate the pulses of the timing signal 310 to a certain number and generate a braking signal 322, and clear the accumulated timing signal 310.

When the frequency and amplitude of the MEMS mirror 10 are stable, its frequency at time t is f(t), and the transmission time of the scanning data 318 in the effective scanning window is T ₂ (or T ₄ ), that is, in the effective scanning window, it should Transmit nβ=1*5102 light spots, as shown in FIG. 9 , that is, at time t, the pulse frequency f _CLK (t) of the timing signal 310 . If at time t, the frequency of the MEMS mirror 10 is 2500 Hz, calculated by Eq. (4), f _CLK =41.22 MHZ. The counting comparator 215 generates 8244 pulse signals within _T2 .

After the frequency T(t) and the amplitude A(t) of the MEMS mirror 10 are correct and stable, the laser controller 23 can start to transmit the scanning data. The method for transmitting the scanning data is shown in Figure 11, which includes the following steps:

S1: If the laser controller 23 sends out the start enable signal 313 to be low potential, then the MEMS scan controller 21 does not send the timing signal 310 and the data brake signal 317a; if the laser controller 23 sends the start enable signal 313 or adjusts signal 314, the MEMS scan controller 21 sends out a first modulation signal 316a, a second modulation signal 316b and a third modulation signal 316c to adjust and judge whether the MEMS mirror 10 is stable. The reflector 10 starts to complete;

S2: After the MEMS mirror 10 stabilizes, the MEMS scanning controller 21 sends a stabilization signal 315;

S3: The MEMS scanning controller 21 sends a timing signal 310; the frequency f _CLK (t) of the timing signal 310 is calculated by Eq. (4);

S4: The laser controller 23 transmits the scan data 318 at a frequency f _CLK (t) of the timing signal 310 .

Thus, the frequency f _CLK (t) of the timing signal 310 is generated by the micro-electromechanical scanning controller 21 for the laser controller 23 to transmit the scanning data 318, because the frequency f _CLK (t) of the timing signal 310 It is calculated and generated by the MEMS scanning controller 21 according to the vibration frequency f(t) of the MEMS mirror 10 at any time t, and can transmit β light spots or its multiple nβ within _T2 or _T4 time light spot. The purpose of this utility model is to provide a kind of micro-electro-mechanical scanning controller 21, make after micro-electro-mechanical mirror 10 stabilizing vibrations, send the frequency f _CLK (t) of sequential signal 310 by micro-electro-mechanical scanning controller 21, reach effectively The scan data 318 is transmitted during the scan window (T ₂ or T ₄ time).

<Embodiment 2> A MEMS laser scanning device of a photoelectric sensor

This embodiment is applied to a micro-electro-mechanical laser scanning device of a photoelectric sensor; the micro-electro-mechanical scanning controller 21 and the control method of this embodiment are the same as those in the first embodiment. In order to make the transmission of the scan data 318 accurate, the data braking signal 317a can be further issued at the same time as the frequency f _CLK (t) of the timing signal 310 sent by the micro-electromechanical scanning controller 21, to drive the laser controller 23 to start transmitting the scan Data 318. As shown in Figure 12, if the logic unit 211 receives the stable signal 315 at the MEMS scan controller 21, it will send a timing signal 310 and a data braking signal 317a; the method for transmitting scan data in this embodiment includes the following steps:

S1: If the laser controller 23 sends out the start enable signal 313 to be low potential, then the MEMS scan controller 21 does not send the timing signal 310 and the data brake signal 317a; if the laser controller 23 sends the start enable signal 313 or adjusts signal 314, the MEMS scan controller 21 sends out a first modulation signal 316a, a second modulation signal 316b and a third modulation signal 316c to adjust and judge whether the MEMS mirror 10 is stable. Mirror 10 starts (sets) and completes;

S2: After the MEMS mirror 10 is stabilized, the MEMS scanning controller 21 will send a stabilization signal 315;

S3: The MEMS scanning controller 21 sends out the timing signal 310 and the data braking signal 317a; the frequency f _CLK (t) of the timing signal 310 is calculated by Eq. (4);

S4: When the laser controller 23 receives the data braking signal 317a, it transmits the scan data 318 at a frequency f _CLK (t) of the timing signal 310 .

<Embodiment 3> A MEMS laser scanning device of a photoelectric sensor

This embodiment is applied to a micro-electro-mechanical laser scanning device of a photoelectric sensor; the micro-electro-mechanical scanning controller 21 and the control method of this embodiment are the same as those in the first embodiment. The MEMS scanning controller 21 of this embodiment further includes an RF delay circuit 216, and the RF delay circuit 216 can delay the input resonance frequency signal 321 until the pulse of the first modulation signal 316a is generated to send out data braking. signal 317b to drive the laser controller 23 to start transmitting the scan data 318 . As shown in Figure 13, if the logic unit 211 receives the stable signal 315 at the MEMS scan controller 21, it will send a timing signal 310 and a data braking signal 317a; the method for transmitting scan data in this embodiment includes the following steps:

S1: If the laser controller 23 sends out the start enable signal 313 to be low potential, then the MEMS scan controller 21 does not send the timing signal 310 and the data braking signal 317b; if the laser controller 23 sends the start enable signal 313 or adjusts signal 314, the MEMS scan controller 21 sends out a first modulation signal 316a, a second modulation signal 316b and a third modulation signal 316c to adjust and judge whether the MEMS mirror 10 is stable. Mirror 10 starts (sets) and completes;

S2: After the MEMS mirror 10 is stabilized, the MEMS scanning controller 21 will send a stabilization signal 315;

S3: The MEMS scan controller 21 sends out the timing signal 310 and the data brake signal 317b; the frequency f _CLK (t) of the timing signal 310 is calculated by Eq. (4);

S4: When the laser controller 23 receives the data braking signal 317 b, it transmits the scan data 318 at a frequency f _CLK (t) of the timing signal 310 .

<Embodiment 4> A MEMS laser scanning device of a photoelectric sensor

This embodiment is applied to a micro-electro-mechanical laser scanning device of a photoelectric sensor; the micro-electro-mechanical scanning controller 21 and the control method of this embodiment are the same as those in the first embodiment. The MEMS scanning controller 21 of this embodiment further includes a data-driven delay circuit 217, and the data-driven delay circuit 217 can transmit the input resonant frequency signal 321 to the first modulation signal 316a when the pulse is generated, In order to be accurate when transmitting the scan data 318, the data drive delay circuit 217 sends a data brake signal 317c at the same time that the microelectromechanical scan controller 21 sends out the frequency f _CLK (t) of the timing signal 310 to drive the laser control The device 23 starts to transmit scan data 318 . As shown in Figure 14, if the logic unit 211 receives the stable signal 315 at the MEMS scan controller 21, it will send a timing signal 310 and a data braking signal 317c; the method for transmitting scan data in this embodiment includes the following steps:

S1: If the laser controller 23 sends out the start enable signal 313 to be low potential, then the MEMS scan controller 21 does not send the timing signal 310 and the data braking signal 317b; if the laser controller 23 sends the start enable signal 313 or adjusts signal 314, the MEMS scan controller 21 sends out a first modulation signal 316a, a second modulation signal 316b and a third modulation signal 316c to adjust and judge whether the MEMS mirror 10 is stable. The reflector 10 starts to complete;

S2: After the MEMS mirror 10 is stabilized, the MEMS scanning controller 21 will send a stabilization signal 315;

S3: The MEMS scanning controller 21 sends out the timing signal 310 and the data braking signal 317c; the frequency f _CLK (t) of the timing signal 310 is calculated by Eq. (4);

S4: When the laser controller 23 receives the data braking signal 317c, it transmits the scan data 318 at a frequency f _CLK (t) of the timing signal 310 .

<Embodiment five> MEMS laser scanning device of two photoelectric sensors

This embodiment is applied to a MEMS laser scanning device with two photoelectric sensors; as shown in FIG. 1 , a photoelectric sensor 14b is provided at θ _p =-21°. In this embodiment, the micro-electromechanical mirror 10 with a frequency f=2500±5%HZ and a maximum scanning angle of ±23° is still used. The micro-electromechanical scanning controller 21 receives the start enable signal 313 of the laser controller 23, receives the adjustment signal 314 of the laser controller 23, generates a first modulation signal 316a for frequency adjustment, generates a second modulation signal 316b for frequency adjustment, Generate a third modulation signal 316c for amplitude adjustment, receive the photoelectric sensing signal 312a sent by the photoelectric sensor 14a and receive the photoelectric sensing signal 312b sent by the photoelectric sensor 14b to detect the resonant frequency of the MEMS mirror 10 and The timing signal 310 is generated to provide to the laser controller 23 to drive the laser light source 11 in good time, so that the scanning light beams 113a to 113b after scanning by the laser light beam 111 are within the effective scanning window, even if the scanning light beams 113a to 113b generate nβ= 5102 light spots (when n=1).

The MEMS scan controller 21 includes a logic unit 211 , D-type flip-flops 212 and 213 , a phase-lock circuit 214 and a counting comparator 215 . The logic unit 211 can receive the trigger photoelectric sensing signal 312a generated by the photoelectric sensor 14a, and calculate the photoelectric sensing signal 312a generated by the photoelectric sensor 14a and the photoelectric sensing signal 312b generated by the photoelectric sensor 14b each time to generate the microelectromechanical The frequency modulation signal and the amplitude modulation signal of the reflector 10, the first modulation signal 316a, the second modulation signal 316b and the third amplitude modulation signal 316c; the phase-lock circuit 214 can generate a timing signal 310, when the laser control The device 23 receives the timing signal 310 sent by the phase-locking circuit 214 of the MEMS scan controller 21, and can send the scan data according to the timing signal 310.

When the MEMS mirror 10 vibrates back and forth, the scanning light 114a will trigger the secondary photoelectric sensor 14a and the scanning light 114b will trigger the secondary photoelectric sensor 14b in each scanning cycle T(t), thus the logic unit 211 The trigger period T(t) of the photoelectric sensing signals 312 a and 312 b is calculated. When controlling T ₁ , T ₂ , T ₃ , and T ₄ , the logic unit 211 of the MEMS scan controller 21 can receive the trigger signal 312a generated by the photoelectric sensor 14a and the trigger signal 312b generated by the photoelectric sensor 14b, and calculate the The trigger signal 312a generated by the sensor 14a and the trigger signal 312b generated by the photoelectric sensor 14b generate the first modulation signal 316a, the second modulation signal 316b and the third modulation signal 316c of the frequency of the MEMS mirror 10; After the first modulation signal 316 a , the second modulation signal 316 b and the third amplitude modulation signal 316 c are sent out, they are received by the bridge circuit 22 to adjust the vibration frequency and amplitude of the MEMS mirror 10 .

After the microelectromechanical mirror 10 reflects the laser light 111, it swings from the left to the right to trigger the photoelectric sensor 14a twice and the time to trigger the photoelectric sensor 14b twice, as shown in Figure 16, the adjacent second trigger photoelectric sensor 14a The time between triggering the photoelectric sensor 14a for the second time and triggering the photoelectric sensor 14b for the first time is TA ₆ , and the ratio to the period T(t) is TA ₆ /(T(t)/2), if the period T(t) follows As time changes, the ratio TA ₆ /(T(t)/2) will also change with time; for the fixed photoelectric sensor 14a and photoelectric sensor 14b, the included angle is _θp , and the maximum scanning angle of the MEMS mirror 10 is θ _c , that is, when the period is T(t), R=TA ₆ /(T(t)/2), or the change of the period T can also be calculated by calculating the change of the ratio R, and the calculation method is as follows:

${\mathrm{TA}}_6\left(t\right)=\frac{T\left(t\right)}{2\mathrm{\&pi;}}\left(2\mathrm{\&pi;}{\sin }^{-1}\left(\frac{{\mathrm{\&theta;}}_p}{{\mathrm{\&theta;}}_c}\right)\right)$ (6)

$R=\frac{{\mathrm{<figure-callout\; id="6"\; label="TA"\; filenames="Y20082000181400191.png,Y20082000181400213.png"\; state="\{\{state\}\}">TA</figure-callout>}}_6}{\frac{1}{2}T}$ same (5)

The method for the MEMS scan controller 21 to control the resonant frequency f(t) and the amplitude A(t) of the MEMS mirror 10 is the same as in the first embodiment, as shown in FIG. 10 . In this embodiment, the photoelectric sensor 14a and the photoelectric sensor 14b are installed at θ _p =21°, that is, when f=2500HZ, according to Eq. (6), it can be calculated that TA ₆ =1.4651×10 ^-4 sec., R =0.73255. In the laser controller 23 controlling the resonant frequency of the MEMS mirror 10 to be f(t) and the amplitude to be A(t), when checking the trigger time ratio of the photoelectric sensing signal 312a, TA ₆ /(T(t)/2 ), that is, the judgment is controlled by R=0.17398～0.19230.

What is shown above is only a preferred embodiment of the present invention, and is only illustrative, not restrictive, of the present invention. Those skilled in the art understand that many changes, modifications, and even equivalent changes can be made within the spirit and scope defined by the claims of the present invention, but all will fall within the protection scope of the present invention.

Claims (8)

1. A micro-electromechanical scanning controller that generates a timing frequency, which is applied to a laser scanning device, and the laser scanning device includes a laser light source for generating laser light, and a micro-electromechanical mirror that utilizes resonance to drive reflection The mirror scans the laser light on the target with forward scanning and reverse scanning, a photoelectric sensor receives the scanning light and converts the light into a photoelectric sensing signal, a bridge circuit for controlling the MEMS mirror and a laser controller It controls the laser light source to emit a laser light source; it is characterized in that: The MEMS scanning controller is used to detect the resonant frequency of the MEMS mirror and generate a timing signal to drive the laser controller to emit a laser light source and scan through the MEMS mirror, including a logic unit, at least one D-type Flip-flop, a phase-locked circuit and a counting comparator, wherein: The logic unit receives the photoelectric sensing signal generated by the photoelectric sensor, and calculates the interval time between each photoelectric sensing signal to generate the frequency modulation signal of the micro-electromechanical mirror, The amplitude modulation signal and the stabilized signal of the MEMS mirror; The D-type flip-flop receives the frequency modulation signal and the amplitude modulation signal generated by the logic unit and generates a resonance frequency signal and a feedback signal; The phase-locked circuit receives the resonant frequency signal generated by the D-type flip-flop and generates a timing signal; The counting comparator receives the timing signal, accumulates the pulses of the timing signal to a certain number and generates a braking signal, and clears the accumulated timing signal, and the braking signal generates the next one via the D-type flip-flop Feedback signal; when the laser light source receives the timing signal sent by the micro-electromechanical scanning controller, the laser controller sends the scanning data within the effective scanning window according to the timing signal. 2 . The MEMS scan controller for generating timing frequency according to claim 1 , wherein the logic unit further sends a data braking signal to drive the laser controller to start transmitting scan data. 3 . 3. The micro-electromechanical scanning controller that generates timing frequency according to claim 1 or 2, is characterized in that: it further comprises an RF delay circuit, and the RF delay circuit uses the D-type flip-flop The output resonance frequency signal is delayed until the frequency modulation signal pulse is generated, and then the data braking signal is sent to drive the laser controller to start transmitting scanning data. 4. The MEMS scanning controller generating timing frequency according to claim 1 or 2, characterized in that: it further comprises a data-driven delay circuit, and said data-driven delay circuit converts said D-type positive The resonant frequency signal output by the inverter is delayed until the frequency modulation signal pulse is generated, and then the data braking signal is sent to drive the laser controller to start transmitting the scanning data. 5. A micro-electro-mechanical scanning controller that generates timing frequencies, which is applied to a laser scanning device, and the laser scanning device includes a laser light source for generating laser light, and a micro-electro-mechanical mirror that uses resonance to drive reflection The mirror scans the laser light on the target with forward scanning and reverse scanning. At least two photoelectric sensors receive the scanning light and convert the light into a photoelectric sensing signal. A bridge circuit that controls the micro-electromechanical mirror and a The laser controller controls the laser light source to emit a laser light source; it is characterized in that: The MEMS scanning controller is used to detect the resonant frequency of the MEMS mirror and generate a timing signal to drive the laser controller to emit a laser light source and scan through the MEMS mirror, including a logic unit, at least one D-type Flip-flop, a phase-locked circuit and a counting comparator, wherein: The logic unit receives photoelectric sensing signals generated by at least two photoelectric sensors, and calculates the interval time between each photoelectric sensing sensing signal to generate the frequency modulation signal of the micro-electromechanical mirror, The amplitude modulation signal and the stabilized signal of the MEMS mirror; The D-type flip-flop receives the frequency modulation signal and the amplitude modulation signal generated by the logic unit and generates a resonance frequency signal and a feedback signal; The phase-locked circuit receives the resonant frequency signal generated by the D-type flip-flop and generates a timing signal; The counting comparator receives the timing signal, accumulates the pulses of the timing signal to a certain number and generates a braking signal, and clears the accumulated timing signal, and the braking signal generates the next one via the D-type flip-flop Feedback signal; when the laser light source receives the timing signal sent by the MEMS scanning controller, the laser controller sends the scanning data within the effective scanning window according to the timing signal. 6 . The MEMS scanning controller for generating timing frequency according to claim 5 , wherein the logic unit further sends a data braking signal to drive the laser controller to start transmitting scanning data. 7 . 7. The micro-electromechanical scanning controller that generates timing frequency according to claim 5 or 6, is characterized in that: it further comprises an RF delay circuit, and the RF delay circuit outputs the resonance of the D-type flip-flop The frequency signal is delayed until the frequency modulation signal pulse is generated, and then the data braking signal is sent to drive the laser controller to start transmitting the scanning data. 8. The MEMS scan controller generating timing frequency according to claim 5 or 6, characterized in that: it further comprises a data-driven delay circuit, and said data-driven delay circuit converts said D-type positive The resonant frequency signal output by the inverter is delayed until the frequency modulation signal pulse is generated, and then the data braking signal is sent to drive the laser controller to start transmitting the scanning data.

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