WO2020087690A1 - 一种信号调整方法及激光扫描投影设备 - Google Patents

一种信号调整方法及激光扫描投影设备 Download PDF

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WO2020087690A1
WO2020087690A1 PCT/CN2018/121749 CN2018121749W WO2020087690A1 WO 2020087690 A1 WO2020087690 A1 WO 2020087690A1 CN 2018121749 W CN2018121749 W CN 2018121749W WO 2020087690 A1 WO2020087690 A1 WO 2020087690A1
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signal
clock
scanning mirror
clock signal
time difference
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French (fr)
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高文刚
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Goertek Inc
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Goertek Inc
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    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/001—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
    • G02B26/10—Scanning systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3141—Constructional details thereof
    • H04N9/315—Modulator illumination systems
    • H04N9/3161—Modulator illumination systems using laser light sources

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  • the present application relates to the field of micro projection technology, and in particular, to a signal adjustment method and a laser scanning projection device.
  • the laser scanning projector (LBS) has a simple structure and small size. The advantages of low optical path loss, low power consumption, wide color range, large contrast, high resolution, and no need to focus.
  • the scanning mirror and laser are the main components.
  • the scanning mirror rotates reciprocally with two orthogonal axes as axes, deflects the combined beam in two perpendicular directions and projects it to a predetermined area to generate a projection image.
  • the scanning mirror includes a micro-motor system (ie, MEMS), and the micro-motor system drives the scanning mirror to reciprocally rotate with two orthogonal axes as axes.
  • the operation in the first direction (commonly referred to as the lateral direction) of the scanning mirror is the line signal HS of the projected image;
  • the operation in the second direction (commonly referred to as the vertical direction) is the frame signal VS of the projected image.
  • the operating frequency in the first direction adopts the resonance frequency of MEMS.
  • the lateral resonance frequency of each MEMS is different; and the resonance frequency shift phenomenon may occur due to temperature changes and the like during long-term operation of MEMS. The difference in resonance frequency or the phenomenon of resonance frequency shift will cause abnormal distortion of the projected image.
  • the present application is proposed to provide a signal adjustment method and a laser scanning projection device that solve the above problems or at least partially solve the above problems.
  • a signal adjustment method includes:
  • the clock frequency of the clock signal that controls the phase of the drive signal is adjusted.
  • a laser scanning projection device in another embodiment of the present application, includes:
  • Clock signal generator used to generate clock signal
  • a driving signal generating unit connected to the clock signal generator, for generating a driving signal for driving the scanning mirror to run in the first direction according to the clock signal;
  • the scanning mirror is connected to the driving signal generating unit and is configured to operate in the first direction under the control of the driving signal;
  • the adjusting unit is connected to the clock signal generator and is used to collect the operating parameters generated during the operation of the scanning mirror in the first direction; determine the time difference between the operating signal and the driving signal; The time difference controls the clock signal generator to adjust the clock frequency of the clock signal it generates.
  • the technical solution provided by the embodiments of the present application acquires the operation status of the scanning mirror by collecting the operation signal generated during the operation of the scanning mirror in the first direction; then, based on the operation signal, the clock signal controlling the phase of the driving signal is adjusted Clock frequency; To ensure that the driving signal of the scanning mirror is always at a relatively stable resonance frequency, to reduce the influence of factors such as differences in the hardware of the device or temperature changes during operation on the image projection effect, and improve the performance of the device.
  • the implementation complexity is low, the hardware performance requirements are not high, and the overall volume of the device is not increased.
  • FIG. 1 is a schematic structural diagram of a laser scanning projection device provided by an embodiment of the present application.
  • FIG. 2 is a signal schematic diagram of a driving signal and a clock signal provided by an embodiment of this application;
  • FIG. 3 is an exemplary diagram of a driving signal provided by an embodiment of the present application to drive a scanning mirror to operate in a first direction;
  • FIG. 4 is a circuit schematic diagram of a laser scanning projection device provided by an embodiment of the present application.
  • FIG. 5 is a schematic flowchart of a signal adjustment method according to an embodiment of the present application.
  • the laser scanning projection device shown in FIG. 1 includes: a laser light source 1, an optical component 2 and a scanning mirror 3.
  • the laser light source 1 is used to emit laser light.
  • the optical component 2 can be used to direct the laser beam emitted by the laser light source to the scanning mirror 3 according to the set optical path, deflect it by the scanning mirror 3, and project it to a predetermined area to generate a projection image.
  • the scanning mirror 3 rotates reciprocally with two orthogonal axes as axes, deflects the projected light beam in two perpendicular directions, and projects it to a predetermined area to generate a projection image.
  • the scanning mirror 3 includes a micro-motor system (MEMS).
  • MEMS micro-motor system
  • the MEMS drives the scanning mirror 3 to reciprocate and rotate about two orthogonal axes as the axis according to the received driving signal, that is, the operation and Running in two directions.
  • the optical component 3 may include: a focusing lens 4, a combined prism 5, a reflecting mirror 6, and the like, which are not specifically limited in this embodiment.
  • the operating frequency of the scanning mirror 3 in the first direction uses the resonance frequency of the MEMS; the resonance frequency of different MEMS is different, affected by temperature changes, etc., so that the operation of the scanning mirror in the first direction cannot be maintained at a relatively high level At a stable resonance frequency, it is necessary to monitor the operation of the scanning mirror in the first direction.
  • the operation of the scanning mirror in the second direction is not involved in the following embodiments, but it does not explain that the scanning mirror mentioned in the following embodiments does not operate in the second direction.
  • the scanning mirror adopts the technical solutions provided by the following embodiments to realize the operation in the first direction, but also needs to operate in the second direction; and the operation of the scanning mirror in the second direction is the same as the prior art
  • the related content in the prior art please refer to the related content in the prior art, which will not be repeated here.
  • FIG. 2 shows a signal diagram of the clock signal Pclk and the drive signal HS.
  • FIG. 2 also shows a signal diagram of the driving signal VS driving the scanning mirror to operate in the second direction.
  • the phase of the driving signal HS is related to the clock signal. Therefore, when the operating frequency of the scanning mirror shifts in the first direction, the phase of the driving signal HS can be changed by adjusting the clock signal Pclk, thereby changing the frequency of the driving signal HS to keep it at the resonance frequency.
  • FIG. 3 shows an exemplary diagram of the driving signal driving the scanning mirror to operate in the first direction.
  • the MEMS drives the scanning mirror to deflect in the first direction.
  • the driving signal may be a sine wave signal (as shown in FIG. 2), or a triangular wave signal (as shown in FIG. 3), etc., which is not specifically limited in this embodiment.
  • the phase value corresponding to the voltage signal fed back by the sensor The phase value of the MEMS drive signal; The inherent phase difference between the MEMS drive signal and the HPZR feedback signal; It is a fixed phase shift caused by LPF and other circuits in the hardware circuit. It can be known from the above formula (1) that the phase value corresponding to the voltage signal fed back by the sensor has a direct relationship with the resonance state of the MEMS. It is feasible to adjust the clock frequency of the clock signal based on the operation signal sensed by the sensor to maintain the operation frequency of the scanning mirror in the first direction to be consistent with the MEMS resonance frequency.
  • the technical solutions of the following embodiments provided by this application are implemented based on the above theory.
  • FIG. 4 shows a circuit schematic diagram of a laser scanning projection device provided by an embodiment of the present application.
  • the laser scanning projection device includes: a clock signal generator 10, a driving signal generating unit 20, a scanning mirror 30 and an adjusting unit 40.
  • the clock signal generator 10 is used to generate a clock signal.
  • the driving signal generating unit 20 is connected to the clock signal generator 10 and generates a driving signal for driving the scanning mirror 30 to operate in the first direction according to the clock signal.
  • the scanning mirror 30 is connected to the driving signal generating unit 20 and is configured to operate in the first direction under the control of the driving signal.
  • the adjusting unit 40 is connected to the clock signal generator 10, and is used to collect the operating parameters generated during the operation of the scanning mirror 30 in the first direction; determine the time difference between the operating signal and the driving signal; According to the time difference, the clock signal generator 10 is controlled to adjust the clock frequency of the clock signal it generates.
  • the technical solution provided in this embodiment acquires the operation status of the scanning mirror by collecting the operation signal generated during the operation of the scanning mirror in the first direction; then, based on the operation signal, the clock of the clock signal that controls the phase of the driving signal is adjusted Frequency; to ensure that the driving signal of the scanning mirror is always at a relatively stable resonance frequency, to reduce the influence of factors such as differences in the hardware of the device or temperature changes during operation on the image projection effect, and improve the performance of the device.
  • the implementation complexity is low, the hardware performance requirements are not high, and the overall volume of the device is not increased.
  • the adjustment unit 40 may include: a sensor 43, a voltage comparator 42, a counter 41 and a controller 44.
  • the sensor 43 is used to generate a corresponding voltage signal when the scanning mirror 30 moves to different positions in the first direction.
  • a voltage comparator 42 is connected to the sensor 43, and is used to compare the voltage signal with a preset voltage signal; and generate a first pulse signal according to the comparison result.
  • the counter 41 is connected to the voltage comparator 42 for acquiring a second pulse signal synchronized with the phase of the driving signal; and determining the time difference according to the first pulse signal and the second pulse signal.
  • the controller 44 is connected to the counter 41 and the clock signal generator 10, and is used to control the clock signal generator 10 to adjust the clock frequency of the clock signal generated according to the time difference.
  • the above-mentioned sensor can generate a corresponding sensing signal when the scanning mirror runs to different positions in the first direction, for example, a piezoelectric sensor is selected.
  • the piezoelectric sensor When the scanning mirror runs to different positions in the first direction, the piezoelectric sensor generates different deformations and generates corresponding voltage signals.
  • controller 44 may be specifically configured to: calculate the phase difference between the operation signal and the drive signal according to the time difference; and calculate the adjusted clock frequency of the clock signal according to the phase difference.
  • the controller 44 is specifically configured to: acquire the phase shift equivalent time inherent in the hardware circuit; calculate the difference between the time difference and the phase shift equivalent time; according to the difference and the clock frequency of the current clock signal To calculate the adjusted clock frequency of the clock signal.
  • the equivalent phase shift time inherent in the hardware circuit is a predictable value, which can be obtained through testing.
  • the processing procedure of the above controller can be simply understood as: taking the difference and the clock frequency of the current clock signal as the input parameters of the calculation model represented by the following formula (2), and executing the calculation model to obtain the adjusted The frequency of the clock signal:
  • (t- ⁇ t) is the difference between the time difference and the phase shift equivalent time; m is the number of sampling points required to form a sinusoidal drive signal; F n-1 is the clock frequency of the clock signal; F n is The frequency of the adjusted clock signal; f () is a preset function.
  • the specific formula of f () can be derived based on the basic theory in the prior art, or it is an empirical formula, which is not specifically limited in this embodiment.
  • the above-mentioned driving signal generating unit may be implemented using the structure shown in FIG. 4.
  • the driving signal generating unit 20 includes a digital waveform generator 21, an analog-to-digital converter 22, and a filter 23.
  • the digital waveform generator 21 is connected to the clock signal generator 10, and is used to generate a digital signal according to the clock signal and preset digital waveform data.
  • An analog-to-digital converter 22 is connected to the digital waveform generator 21 and is used to convert the digital signal into an analog signal.
  • the filter 23 is connected to the analog-to-digital converter 22 and the scanning mirror 30 and is used to filter the analog signal; the filtered analog signal is used as the driving signal to drive the scanning mirror 30 Running in the first direction.
  • the digital waveform generator 21 may include: a phase accumulator 211 and a sine wave waveform table 213.
  • the phase accumulator 211 is connected to the clock signal generator 10 and is used to control the phase of the digital signal to be generated under the driving of the clock signal;
  • the driving waveform table 212 stores the digital waveform data of the driving signal
  • the number of data is m
  • m is the number of sampling points needed to form a sine wave signal.
  • the specific value of m is a set value, which may be an empirical value or an artificial set value, etc., which is not specifically limited in this embodiment.
  • the digital waveform generator 21 also outputs a second pulse signal synchronized with the phase of the driving signal to the counter, so that the counter can determine the second pulse signal as the time difference Reference signal.
  • the digital waveform data may be digital waveform data corresponding to a sine wave waveform, or digital waveform data corresponding to a square wave waveform, etc., which is not specifically limited in this embodiment.
  • the above-mentioned filter 23 may be a low-pass filter to filter out high-frequency interference signals in the analog signal.
  • the technical solution provided by this embodiment can accurately and effectively monitor the frequency of the scanning mirror running in the first direction at the resonance frequency, and the hardware complexity only by simple acquisition, comparison, calculation, etc. Low, will not increase the size of the device.
  • the technical solution provided by this embodiment can effectively reduce the performance requirements of MEMS control.
  • FIG. 5 shows a schematic flowchart of a signal adjustment method provided by an embodiment of the present application.
  • the execution subject of the signal adjustment method provided in this embodiment may be provided in an adjustment unit in a laser scanning projection device.
  • the signal adjustment method includes:
  • the operation signal may be generated by a sensor provided in the laser scanning projection device for monitoring the operation of the scanning mirror in the first direction.
  • the sensor is a piezoelectric sensor, and the scanning mirror moves to different positions in the first direction, and the piezoelectric sensor will generate a corresponding deformation, and then generate a corresponding voltage signal.
  • the above 102 determine the time difference between the operation signal and the driving signal based on the driving signal of the scanning mirror operating in the first direction” may specifically adopt the following steps achieve:
  • the above 103 can be implemented in the following two ways:
  • Method 1 Based on the time difference, calculate the phase difference between the operation signal and the drive signal; based on the phase difference, calculate the adjusted clock frequency of the clock signal.
  • Method 2 Obtain the phase shift equivalent time inherent in the hardware circuit; calculate the difference between the time difference and the phase shift equivalent time; calculate the adjusted clock according to the difference and the clock frequency of the current clock signal The clock frequency of the signal.
  • f () is the preset function. In specific implementation, the specific formula of f () can be derived based on the basic theory in the prior art, or it is an empirical formula, which is not specifically limited in this embodiment.
  • the technical solution provided in this embodiment acquires the operating conditions of the scanning mirror by collecting the operating signals generated during the operation of the scanning mirror in the first direction; and then adjusts the clock of the clock signal that controls the phase of the driving signal based on the operating signals Frequency; to ensure that the driving signal of the scanning mirror is always at a relatively stable resonance frequency, to reduce the influence of factors such as differences in the hardware of the device or temperature changes during operation on the image projection effect, and improve the performance of the device.
  • the implementation complexity is low, the hardware performance requirements are not high, and the overall volume of the device is not increased.
  • the method provided by the embodiment of the present application may further include the following steps:
  • the preset digital waveform data may be digital waveform data corresponding to a sine wave waveform or digital waveform data corresponding to a square wave waveform, etc., which is not specifically limited in this embodiment.
  • a low-pass filter may be used to filter the analog signal to filter out high-frequency interference signals.

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Abstract

一种信号调整方法及激光扫描投影设备。其中，信号调整方法包括如下的步骤：采集扫描镜(3)在第一方向上运转过程中所产生的运转信号；基于扫描镜(3)在第一方向上运转的驱动信号，确定运转信号与驱动信号的时间差；根据时间差，调整控制驱动信号相位的时钟信号的时钟频率。可保证扫描镜(3)的驱动信号一直处于一个较为稳定的共振频率上，以降低因设备硬件存在的差异性或运转时因温度变化等因素对图像投影效果的影响，提高设备性能。实现复杂度低，对硬件性能要求不高，不会增大设备的整体体积。

Description

一种信号调整方法及激光扫描投影设备 技术领域
本申请涉及微型投影技术领域，尤其涉及一种信号调整方法及激光扫描投影设备。
背景技术
相比常见的LCD(液晶微型投影技术)透射微投影、DLP(数字光学处理技术)反射式微投影及LCOS(硅基液晶)反射式微投影，激光扫描投影仪(LBS)具有结构简单、体积小、光路损耗小、功耗低、色彩范围广、对比度大、分辨率高、无需对焦等优点。
LBS投影系统中，扫描镜与激光器是主要的组成部件。其中，扫描镜分别以正交的两个轴为轴线往复旋转，将合束后的光束沿垂直的两个方向偏转后投影到预定区域，生成投影图像。扫描镜包括微电机系统(即MEMS),微电机系统驱动该扫描镜以正交的两个轴为轴线往复旋转。
扫描镜的第一方向(通常称为横向)上的运转为投影图像的行信号HS；第二方向(通常称为纵向)上的运转为投影图像的帧信号VS。为降低系统的功耗，第一方向上的运转频率采用MEMS的共振频率。然而，在生产中MEMS存在一定差异性，各MEMS的横向共振频率存在差异性；且MEMS长时间运转会因为温度变化等出现共振频率偏移现象。共振频率存在的差异或共振频率偏移的现象，会致使投影图像畸变异常。
发明内容
鉴于上述问题，提出了本申请以提供一种解决上述问题或至少部分地解决上述问题的一种信号调整方法及激光扫描投影设备。
在本申请的一个实施例中，提供了一种信号调整方法。该方法包括：
采集所述扫描镜在第一方向上运转过程中所产生的运转信号；
基于所述扫描镜在所述第一方向上运转的驱动信号，确定所述运转信号与驱动信号的时间差；
根据所述时间差，调整控制所述驱动信号相位的时钟信号的时钟频率。
在本申请的另一个实施例中，提供了一种激光扫描投影设备。该激光扫描投影设备，包括：
时钟信号发生器，用于产生时钟信号；
驱动信号发生单元，与所述时钟信号发生器连接，用于根据所述时钟信号，生成驱动扫描镜在第一方向上运转的驱动信号；
所述扫描镜，与所述驱动信号发生单元连接，用于在所述驱动信号的控制下在所述第一方向上运转；
调整单元，与所述时钟信号发生器连接，用于采集所述扫描镜在所述第一方向上运转过程中产生的运转参数；确定所述运转信号与所述驱动信号的时间差；根据所述时间差，控制所述时钟信号发生器调整其产生的时钟信号的时钟频率。
本申请实施例提供的技术方案，通过采集扫描镜在第一方向上运转过程中产生的运转信号，以获知扫描镜的运转状况；然后基于运转信号，调整控制所述驱动信号相位的时钟信号的时钟频率；以保证扫描镜的驱动信号一直处于一个较为稳定的共振频率上，以降低因设备硬件存在的差异性或运转时因温度变化等因素对图像投影效果的影响，提高设备性能。另外，采用本申请实施例提供的技术方案，实现复杂度低，对硬件性能要求不高，不会增大设备的整体体积。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作一简单地介绍，显而易见地，下面描述中的附图是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为本申请一实施例提供的激光扫描投影设备的原理性结构图；
图2为本申请一实施例提供的驱动信号与时钟信号的信号示意图；
图3为本申请一实施例提供的驱动信号驱动扫描镜在第一方向上运转的示例性示图；
图4为本申请一实施例提供的激光扫描投影设备的电路原理图；
图5为本申请一实施例提供的信号调整方法的流程示意图。
具体实施方式
下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述。显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
在介绍本申请实施例提供的技术方案之前，先对激光扫描投影设备的结构作一个简单介绍。
如图1所示的激光扫描投影设备，包括：激光光源1、光学组件2和扫描镜3。其中，激光光源1用于发射激光。具体实施时，激光光源1可为三个，分别为红绿蓝三色激光光源，用于提供红绿蓝三种衍射的激光束以投影生成彩色图像。光学组件2可用于将激光光源发出的激光光束按照设定光路至扫描镜3，再经扫描镜3偏转后，投影到预定区域生成投影图像。扫描镜3分别以正交的两个轴为轴线往复旋转，将投射来的光束沿垂直的两个方向偏转后投影到预定区域，生成投影图像。扫描镜3包括微电机系统(MEMS)， MEMS根据接收到的驱动信号，驱动扫描镜3以正交的两个轴为轴线往复旋转，即上述内容中提及的第一方向上的运转及第二方向上的运转。
这里需要说明的是：光学组件3可包括：聚焦透镜4、组合型棱镜5、反射镜6等等，本实施例对此不作具体限定。
由于扫描镜3在第一方向上的运转频率采用的是MEMS的共振频率；不同MEMS的共振频率存在差异、受温度变化影响等等，使得扫描镜在第一方向上的运转不能维持在一个较为稳定的共振频率上，所以需要对扫描镜在第一方向上的运转情况进行监控。而扫描镜在第二方向上的运转，在下述各实施例中并不涉及，但并不说明下述各实施例中提及的扫描镜不作第二方向上的运转。可以理解的是：扫描镜采用如下各实施例提供的技术方案实现在第一方向上的运转外，也需在第二方向上运转；而扫描镜在第二方向上的运转同现有技术，详细内容可参见现有技术中的相关内容，本文不再赘述。
图2示出了时钟信号Pclk、驱动信号HS的信号图。该图2中还示出了驱动扫描镜在第二方向运转的驱动信号VS的信号图。从图2可知，驱动信号HS的相位与时钟信号相关。因此，当扫描镜在第一方向上的运转频率发生偏移时，通过调整时钟信号Pclk即可改变驱动信号HS的相位，进而改变驱动信号HS的频率以使其保持在共振频率。
图3示出了驱动信号驱动扫描镜在第一方向上运转的示例性示图。在驱动信号的控制下，MEMS带动扫描镜在第一方向上发生偏转。这里需要说明的是：驱动信号可以是正弦波信号(如图2所示)、也可以是三角波信号(如图3所示)等等，本实施例对此不作具体限定。
因为扫描镜在第一方向上的运转是采用与MEMS谐振频率一致的正弦信号驱动的。MEMS处于共振状态，所以相位会有：
Figure PCTCN2018121749-appb-000001
其中，
Figure PCTCN2018121749-appb-000002
为传感器反馈的电压信号对应的相位值；
Figure PCTCN2018121749-appb-000003
为MEMS驱动信号的相位值；
Figure PCTCN2018121749-appb-000004
为MEMS驱动信号与HPZR反馈信号固有相位差；
Figure PCTCN2018121749-appb-000005
为硬件电路中LPF等电路造成的固定相移。通过上述公式(1)可知，传感器反馈的电压信号对应的相位值与MEMS的共振状态有直接的关系。基于传感器感测的运转信号来调整时钟信号的时钟频率，以维持扫描镜在第一方向上的运转频率于MEMS谐振频率一致的方案是可行的。本申请提供的如下各实施例的技术方案，即基于上述理论实现。
图4示出了本申请一实施例提供的激光扫描投影设备的电路原理图。具体的，如图4所示，所述激光扫描投影设备包括：时钟信号发生器10、驱动信号发生单元20、扫描镜30及调整单元40。其中，时钟信号发生器10用于产生时钟信号。驱动信号发生单元20，与所述时钟信号发生器10连接，用于根据所述时钟信号，生成驱动扫描镜30在第一方向上运转的驱动信号。扫描镜30，与所述驱动信号发生单元20连接，用于在所述驱动信号的控制下在所述第一方向上运转。调整单元40，与所述时钟信号发生器10连接，用于采集所述扫描镜30在所述第一方向上运转过程中产生的运转参数；确定所述运转信号与所述驱动信号的时间差；根据所述时间差，控制所述时钟信号发生器10调整其产生的时钟信号的时钟频率。
本实施例提供的技术方案，通过采集扫描镜在第一方向上运转过程中产生的运转信号，以获知扫描镜的运转状况；然后基于运转信号，调整控制所述驱动信号相位的时钟信号的时钟频率；以保证扫描镜的驱动信号一直处于一个较为稳定的共振频率上，以降低因设备硬件存在的差异性或运转时因温度变化等因素对图像投影效果的影响，提高设备性能。另外，采用本申请实施例提供的技术方案，实现复杂度低，对硬件性能要求不高，不会增大设备的整体体积。
在一种可实现的技术方案中，所述调整单元可采用图4所示的结构实现。参见图4，所述调整单元40可包括：传感器43、电压比较器42、计数器41及控制器44。其中，传感器43，用于在所述扫描镜30在所述第一方向上运转到不同位置时产生对应的电压信号。电压比较器42，与所述传感器43连接，用于将所述电压信号与预置电压信号进行比较；根据比较结果生成第一 脉冲信号。计数器41，与所述电压比较器42连接，用于获取与所述驱动信号相位同步的第二脉冲信号；根据所述第一脉冲信号及所述第二脉冲信号，确定所述时间差。控制器44，与所述计数器41及所述时钟信号发生器10连接，用于根据所述时间差，控制所述时钟信号发生器10调整其产生的时钟信号的时钟频率。
具体实施时，上述传感器能在扫描镜在第一方向上运转至不同位置时产生对应的感测信号，例如，选用压电传感器。扫描镜在第一方向上运转至不同位置时，压电传感器产生不同形变进而生成对应的电压信号。
进一步的，上述控制器44可具体用于：根据所述时间差，计算得到所述运转信号与所述驱动信号的相位差；根据所述相位差，计算调整后的所述时钟信号的时钟频率。
或者，所述控制器44具体用于：获取硬件电路固有的相移等效时间；计算所述时间差与所述相移等效时间的差值；根据所述差值及当前时钟信号的时钟频率，计算调整后的所述时钟信号的时钟频率。其中，硬件电路固有的相移等效时间为一预知值，可通过测试得到。具体实施时，上述控制器的处理过程可简单的理解为：将所述差值及当前时钟信号的时钟频率作为如下公式(2)表征的计算模型的入参，执行该计算模型得到调整后的所述时钟信号的频率：
Figure PCTCN2018121749-appb-000006
其中，(t-Δt)为所述时间差与所述相移等效时间的差值；m为组成一个正弦驱动信号所需要的取样点数；F n-1为时钟信号的时钟频率；F n为调整后的所述时钟信号的频率；f()为预置函数。具体实施时，f()的具体公式实现可基于现有技术中的基础理论推导得到，或者为一个经验公式，本实施例对此不作具体限定。
在一种可实现的技术方案中，上述驱动信号发生单元可采用图4所示的结构实现。具体的，参见图4，所述驱动信号发生单元20包括：数字波形生 成器21、模数转换器22及滤波器23。其中，数字波形生成器21，与所述时钟信号发生器10连接，用于根据所述时钟信号及预置的数字波形数据，生成数字信号。模数转换器22，与所述数字波形生成器21连接，用于将所述数字信号转换为模拟信号。滤波器23，与所述模数转换器22及所述扫描镜30连接，用于对所述模拟信号进行滤波；将滤波后的所述模拟信号作为所述驱动信号以驱动所述扫描镜30在所述第一方向上的运转。
进一步的，数字波形生成器21可包括：相位累加器211及正弦波波形表格213。其中，相位累加器211，与所述时钟信号发生器10连接，用于在所述时钟信号的驱动下，控制欲生成的数字信号的相位；驱动波形表格212内存储有驱动信号的数字波形数据，数据个数为m，m为组成一个正弦波信号所需的取样点数。其中，m的具体取值为一设定值，其可以是一个经验值或人为设定值等等，本实施例对此不作具体限定。
再进一步，上述数字波形生成器21除输出作为驱动信号的数字信号外，还向计数器输出与所述驱动信号相位同步的第二脉冲信号，以便于计数器将所述第二脉冲信号作为时间差确定的参照信号。
具体实施时，上述数字波形数据可以是正弦波波形对应的数字波形数据，也可以是方波波形对应的数字波形数据，等等，本实施例对此不作具体限定。上述滤波器23可以低通滤波器，以将所述模拟信号中的高频干扰信号滤除。
有上述内容可知，本实施例提供的技术方案，仅需通过简单的采集、比较、计算等，即可准确有效的监控扫描镜在第一方向上运转的频率在共振频率上，且硬件复杂度低、不会增大设备的体积。另外，本实施例提供的技术方案，能够有效降低MEMS控制的性能要求。
图5示出了本申请一实施例提供的信号调整方法的流程示意图。本实施例提供的所述信号调整方法的执行主体可以设置在激光扫描投影设备中的调整单元。具体的，如图5所示，信号调整方法包括：
101、采集所述扫描镜在第一方向上运转过程中所产生的运转信号。
102、基于所述扫描镜在所述第一方向上运转的驱动信号，确定所述运转信号与驱动信号的时间差。
103、根据所述时间差，调整控制所述驱动信号相位的时钟信号的时钟频率。
上述101中，运转信号可以是设置在激光扫描投影设备中用于监测扫描镜在第一方向上运转情况的传感器生成的。例如，该传感器为压电传感器，扫描镜在第一方向上运转到不同位置，压电传感器会产生相应的形变，进而生成相应的电压信号。
当所述运转信号为传感器采集到的电压信号时，上述102“基于所述扫描镜在所述第一方向上运转的驱动信号，确定所述运转信号与驱动信号的时间差”可具体采用如下步骤实现：
1021、将所述电压信号与预置电压信号进行比较。
1022、根据比较结果，生成第一脉冲信号。
1023、获取与所述驱动信号相位同步的第二脉冲信号。
1024、根据所述第一脉冲信号及所述第二脉冲信号，确定所述时间差。
上述103可采用如下两种方式实现：
方式一、根据所述时间差，计算得到所述运转信号与所述驱动信号的相位差；根据所述相位差，计算调整后的所述时钟信号的时钟频率。
方式二、获取硬件电路固有的相移等效时间；计算所述时间差与所述相移等效时间的差值；根据所述差值及当前时钟信号的时钟频率，计算调整后的所述时钟信号的时钟频率。
即上述方式二的实现过程可简单理解为采用如下计算公式实现：
Figure PCTCN2018121749-appb-000007
其中，t为计数器单元计算的时间差；Δt为硬件电路固有的相移等效时间；m为组成一个正弦驱动信号所需要的取样点数；F n与F n-1为时钟信号的时钟频率。f()为预置函数。具体实施时，f()的具体公式实现可基于现有技术中的 基础理论推导得到，或者为一个经验公式，本实施例对此不作具体限定。
本实施例提供的技术方案，通过采集扫描镜在第一方向上运转过程中产生的运转信号，以获知扫描镜的运转状况；然后基于运转信号，调整控制所述驱动信号相位的时钟信号的时钟频率；以保证扫描镜的驱动信号一直处于一个较为稳定的共振频率上，以降低因设备硬件存在的差异性或运转时因温度变化等因素对图像投影效果的影响，提高设备性能。另外，采用本申请实施例提供的技术方案，实现复杂度低，对硬件性能要求不高，不会增大设备的整体体积。
进一步的，本申请实施例提供的所述方法还可包括如下步骤：
104、按照调整频率后的所述时钟信号及预置的数字波形数据，生成数字信号。
其中，预置的数字波形数据可以是正弦波波形对应的数字波形数据或方波波形对应的数字波形数据，等等，本实施例对此不作具体限定。
105、将所述数字信号转换为模拟信号。
106、对所述模拟信号进行滤波。
具体实施时，可采用低通滤波器实现对模拟信号的滤波，以滤除高频干扰信号。
107、将滤波后的所述模拟信号作为所述驱动信号，以驱动所述扫描镜在所述第一方向上的运转。
这里需要说明的是，本实施例提供的所述方法是在上述激光扫描投影设备实施例提供的硬件基础上实现的。
在本申请的说明书、权利要求书及上述附图中描述的一些流程中，包含了按照特定顺序出现的多个操作，这些操作可以不按照其在本文中出现的顺序来执行或并行执行。操作的序号如101、102等，仅仅是用于区分各个不同的操作，序号本身不代表任何的执行顺序。另外，这些流程可以包括更多或更少的操作，并且这些操作可以按顺序执行或并行执行。需要说明的是，本文中的“第一”、“第二”等描述，是用于区分不同的信号、设备、模块等，不 代表先后顺序，也不限定“第一”和“第二”是不同的类型。
最后应说明的是：以上实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的精神和范围。

Claims (10)

  1. 一种信号调整方法，其特征在于，包括：
    采集所述扫描镜在第一方向上运转过程中所产生的运转信号；
    基于所述扫描镜在所述第一方向上运转的驱动信号，确定所述运转信号与驱动信号的时间差；
    根据所述时间差，调整控制所述驱动信号相位的时钟信号的时钟频率。
  2. 根据权利要求1所述的方法，其特征在于，所述运转信号为传感器采集到的电压信号；以及
    基于所述扫描镜在所述第一方向上运转的驱动信号，确定所述运转信号与驱动信号的时间差，包括：
    将所述电压信号与预置电压信号进行比较；
    根据比较结果，生成第一脉冲信号；
    获取与所述驱动信号相位同步的第二脉冲信号；
    根据所述第一脉冲信号及所述第二脉冲信号，确定所述时间差。
  3. 根据权利要求1或2所述的方法，其特征在于，根据所述时间差，调整所述时钟信号的时钟频率，包括：
    根据所述时间差，计算得到所述运转信号与所述驱动信号的相位差；
    根据所述相位差，计算调整后的所述时钟信号的频率。
  4. 根据权利要求1或2所述的方法，其特征在于，根据所述时间差，调整所述时钟信号的时钟频率，包括：
    获取硬件电路固有的相移等效时间；
    计算所述时间差与所述相移等效时间的差值；
    根据所述差值及当前时钟信号的频率，计算调整后的所述时钟信号的频率。
  5. 根据权利要求1或2所述的方法，其特征在于，还包括：
    按照调整频率后的所述时钟信号及预置的数字波形数据，生成数字信号；
    将所述数字信号转换为模拟信号；
    对所述模拟信号进行滤波；
    将滤波后的所述模拟信号作为所述驱动信号，以驱动所述扫描镜在所述第一方向上的运转。
  6. 一种激光扫描投影设备，其特征在于，包括：
    时钟信号发生器，用于产生时钟信号；
    驱动信号发生单元，与所述时钟信号发生器连接，用于根据所述时钟信号，生成驱动扫描镜在第一方向上运转的驱动信号；
    所述扫描镜，与所述驱动信号发生单元连接，用于在所述驱动信号的控制下在所述第一方向上运转；
    调整单元，与所述时钟信号发生器连接，用于采集所述扫描镜在所述第一方向上运转过程中产生的运转参数；确定所述运转信号与所述驱动信号的时间差；根据所述时间差，控制所述时钟信号发生器调整其产生的时钟信号的时钟频率。
  7. 根据权利要求6所述的激光扫描投影设备，其特征在于，所述调整单元包括：
    传感器，用于在所述扫描镜在所述第一方向上运转到不同位置时产生对应的电压信号；
    电压比较器，与所述传感器连接，用于将所述电压信号与预置电压信号进行比较；根据比较结果生成第一脉冲信号；
    计数器，与所述电压比较器连接，用于获取与所述驱动信号相位同步的第二脉冲信号；根据所述第一脉冲信号及所述第二脉冲信号，确定所述时间差；
    控制器，与所述计数器及所述时钟信号发生器连接，用于根据所述时间差，控制所述时钟信号发生器调整其产生的时钟信号的时钟频率。
  8. 根据权利要求7所述的激光扫描投影设备，其特征在于，
    所述控制器，还用于根据所述时间差，计算得到所述运转信号与所述驱动信号的相位差；根据所述相位差，计算调整后的所述时钟信号的时钟频率。
  9. 根据权利要求7所述的激光扫描投影设备，其特征在于，
    所述控制器，还用于获取硬件电路固有的相移等效时间；计算所述时间差与所述相移等效时间的差值；根据所述差值及当前时钟信号的时钟频率，计算调整后的所述时钟信号的时钟频率。
  10. 根据权利要求6至9中任一项所述的激光扫描投影设备，其特征在于，所述驱动信号发生单元包括：
    数字波形生成器，与所述时钟信号发生器连接，用于根据所述时钟信号及预置的数字波形数据，生成数字信号；
    模数转换器，与所述数字波形生成器连接，用于将所述数字信号转换为模拟信号；
    滤波器，与所述模数转换器及所述扫描镜连接，用于对所述模拟信号进行滤波；将滤波后的所述模拟信号作为所述驱动信号以驱动所述扫描镜在所述第一方向上的运转。
PCT/CN2018/121749 2018-10-31 2018-12-18 一种信号调整方法及激光扫描投影设备 Ceased WO2020087690A1 (zh)

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Families Citing this family (3)

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Publication number Priority date Publication date Assignee Title
CN110806638B (zh) * 2019-10-08 2022-09-09 歌尔光学科技有限公司 微振镜共振频率的确定方法、装置及计算机存储介质
CN110850586A (zh) * 2019-10-21 2020-02-28 歌尔股份有限公司 振镜扫描中激光器的控制系统
CN113176550B (zh) 2019-12-30 2023-04-07 上海禾赛科技有限公司 用于扫描振镜的帧同步方法和激光雷达

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010097092A (ja) * 2008-10-20 2010-04-30 Canon Inc 揺動体装置、揺動体装置を用いた偏向装置、及び揺動体装置の制御方法
JP2012053216A (ja) * 2010-08-31 2012-03-15 Brother Ind Ltd 走査型画像表示装置
JP2012078392A (ja) * 2010-09-30 2012-04-19 Brother Ind Ltd 走査型画像表示装置
CN103813118A (zh) * 2012-11-08 2014-05-21 索尼公司 驱动控制装置和驱动控制方法以及视频输出装置
US20160018256A1 (en) * 2014-07-18 2016-01-21 Funai Electric Co., Ltd. Laser scanner
CN106463088A (zh) * 2014-05-16 2017-02-22 日立麦克赛尔株式会社 扫描型显示装置

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7972014B2 (en) * 2008-08-05 2011-07-05 Opus Microsystems Corporation Scanning projection apparatus with phase detection and compensation
DE102008049477A1 (de) * 2008-09-29 2010-04-08 Osram Gesellschaft mit beschränkter Haftung Verfahren und Vorrichtung zur Projektion mindestens eines Lichtstrahls
JP2010261979A (ja) * 2009-04-30 2010-11-18 Funai Electric Co Ltd レーザプロジェクタ
CN104883549B (zh) * 2014-02-28 2017-03-15 光宝电子(广州)有限公司 扫描投影机及其扫描影像的同步方法
JP6754074B2 (ja) * 2015-03-31 2020-09-09 ミツミ電機株式会社 光走査制御装置
US9693029B1 (en) * 2015-12-22 2017-06-27 Microvision, Inc. System and method for feedback control in scanning projectors
CN109587461B (zh) * 2018-10-26 2020-11-17 歌尔光学科技有限公司 激光扫描投影设备及其投影方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010097092A (ja) * 2008-10-20 2010-04-30 Canon Inc 揺動体装置、揺動体装置を用いた偏向装置、及び揺動体装置の制御方法
JP2012053216A (ja) * 2010-08-31 2012-03-15 Brother Ind Ltd 走査型画像表示装置
JP2012078392A (ja) * 2010-09-30 2012-04-19 Brother Ind Ltd 走査型画像表示装置
CN103813118A (zh) * 2012-11-08 2014-05-21 索尼公司 驱动控制装置和驱动控制方法以及视频输出装置
CN106463088A (zh) * 2014-05-16 2017-02-22 日立麦克赛尔株式会社 扫描型显示装置
US20160018256A1 (en) * 2014-07-18 2016-01-21 Funai Electric Co., Ltd. Laser scanner

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