本发明的最佳实施方式BEST MODE FOR CARRYING OUT THE INVENTION
在以下的叙述中,为了使读者更好地理解本申请而提出了许多技术细节。但是,本领域的普通技术人员可以理解,即使没有这些技术细节和基于以下各实施方式的种种变化和修改,也可以实现本申请各权利要求所要求保护的技术方案。In the following description, numerous technical details are set forth in order to provide the reader with a better understanding of the present application. However, those skilled in the art can understand that the technical solutions claimed in the claims of the present application can be implemented without these technical details and various changes and modifications based on the following embodiments.
为使本发明的目的、技术方案和优点更加清楚,下面将结合附图对本发明的实施方式作进一步地详细描述。The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.
可以应用本发明技术方案的一种光学引擎的结构如图1所示,该光学引擎为反射型,包括:R光源(10R),G光源(10G),B光源(10B),分色镜50R、40G、50B,漫射体(20),光束整形器(Beam
Shaper)(30),物镜(40-1,40-2),光调制器(60),投射透镜(70),偏振分光镜(80),其中R代表红色,G代表绿色,B代表蓝色。The structure of an optical engine to which the technical solution of the present invention can be applied is as shown in FIG. 1. The optical engine is of a reflective type, including: an R light source (10R), a G light source (10G), a B light source (10B), and a dichroic mirror 50R. , 40G, 50B, diffuser (20), beam shaper (Beam
Shaper) (30), objective lens (40-1, 40-2), light modulator (60), projection lens (70), polarization beam splitter (80), where R stands for red, G stands for green, and B stands for blue .
R/G/B光源依次照射R/G/B光,具体地说,把照射一个帧的时间设为T,T/3的时间照射R光源,接着的T/3的时间照射G光源,再接着的T/3时间照射B光源。可以理解,光源也可以按照其它顺序依次照射,如B/G/R等。The R/G/B light source sequentially illuminates the R/G/B light. Specifically, the time for irradiating one frame is set to T, the time of T/3 is irradiated to the R light source, and the time of the next T/3 is irradiated with the G light source, and then The next T/3 time illuminates the B source. It can be understood that the light source can also be sequentially irradiated in other orders, such as B/G/R.
微型投影机用的光源,既要体积小也要发光多,因此需要使用激光光源。三个光源(10R,10G,10B)被各自的分色镜50R,50G,50B反射或是透射到漫射体(20)。The light source used in the micro projector requires a small volume and a large amount of light, so a laser light source is required. The three light sources (10R, 10G, 10B) are reflected by the respective dichroic mirrors 50R, 50G, 50B or transmitted to the diffuser (20).
分色镜50G起到反射G光源(从10G照射出的绿色激光)并让剩余光线透过的作用,分色镜50G也可以使用能够将普通可视光线全部予以反射的一般镜子。分色镜50R起到反射R光源(从10R照射出的红色激光)、通过剩余波长范围的光线的作用,分色镜50B起到反射R光源(从10B照射出的蓝色激光)通过剩余波长范围光线的作用。The dichroic mirror 50G functions to reflect the G light source (green laser light emitted from 10G) and transmit the remaining light. The dichroic mirror 50G can also use a general mirror that can reflect all of the ordinary visible light. The dichroic mirror 50R functions to reflect the R light source (red laser light emitted from 10R) and pass the light of the remaining wavelength range, and the dichroic mirror 50B functions to reflect the R light source (the blue laser light emitted from 10B) through the remaining wavelength. The effect of the range of light.
漫射体(20)垂直于光轴振动,因此通过漫射体(20)的时候,光的随机性(Randomness)会得到增加。这种漫射体,是为了消除激光特有的激光散斑(Speckle)而设置的装置,用以减少激光光线的连贯性(Coherence)特征来达到减少激光散斑的目的。The diffuser (20) vibrates perpendicular to the optical axis, so the randomness of the light increases as it passes through the diffuser (20). This diffuser is a device designed to eliminate laser-specific laser speckles (Speckle) to reduce the coherence of laser light to reduce laser speckle.
通过漫射体(20)的光会通过光束整形器(30)来转变光束形状。转变光束形状的原因是要将光束的模样整形成适应于光调制器(60)的入射面形状以提高光效率。Light passing through the diffuser (20) will transform the beam shape through the beam shaper (30). The reason for changing the shape of the beam is to shape the pattern of the beam to the shape of the incident surface of the light modulator (60) to improve the light efficiency.
图1中的实例中光束整形器(30)使用了两面由小型透镜体构成的复眼透镜,也可以使用2枚单面透镜。在这样的两面,或者是两枚上面各自聚集成型的多个小型透镜体会相互之间一一对应来成形。这样的光速整形器把以100至200微米直径大小入射的激光,转换成面状态并扩大,可缓和激光的连贯特性,并把光能量扩散成面光,可降低因为集中在一起产生的激光特有的危险性。In the example of Fig. 1, the beam shaper (30) uses a fly-eye lens composed of a small lens body on both sides, and two single-sided lenses may be used. On such two sides, or a plurality of small lens bodies each formed by aggregating them on one another, they are formed in one-to-one correspondence with each other. Such a light-speed shaper converts a laser incident at a diameter of 100 to 200 μm into a surface state and expands, which can alleviate the coherence characteristics of the laser and diffuse the light energy into a surface light, thereby reducing the specificity of the laser light generated by the concentration together. The danger.
包含在复眼透镜的小型透镜体可以是多种形状:比如四角凸透镜形状,六角凸透镜形状或者圆形等,不过最好是和光调制器的有效区域形状一致。比如说光调制器的有效区域形状是四角形的时候,小型透镜体的形状也做成四角形能把光损失将到最低。The small lens body included in the fly-eye lens may have various shapes such as a quadrangular convex lens shape, a hexagonal convex lens shape or a circular shape, etc., but preferably conforms to the effective area shape of the light modulator. For example, when the effective area of the light modulator is quadrangular, the shape of the small lens body is also quadrangular to minimize light loss.
小透镜体的直径最好为80-500um,这个尺寸下光束更容易整形。这是因为小型透镜的直径小于80um的话会因为激光的连贯性在光束里产生格子纹路,并且在现有技术下很难制做出比80um还小的光滑面的透镜构造。直径变大的话光束整形器的效果会减弱,得不到超小型光学引擎所需的均匀光源,所以用500um以下为好。The diameter of the lenslet body is preferably 80-500 um, and the beam is more easily shaped at this size. This is because the diameter of the small lens is less than 80 um, and the lattice pattern is generated in the light beam due to the continuity of the laser, and it is difficult to make a lens configuration having a smooth surface smaller than 80 um in the prior art. When the diameter is increased, the effect of the beam shaper is weakened, and the uniform light source required for the ultra-small optical engine is not obtained, so it is preferable to use 500 um or less.
各小透镜体由多种不同大小的小透镜混合组成,从而使激光散斑得以减少。Each lenslet body is composed of a mixture of lens lenses of various sizes, thereby reducing laser speckle.
物镜(40)是将经过光束整形器整形的光线利用光调制器(60)进行集束的透镜,一般由一至两片组成。The objective lens (40) is a lens that bundles light shaped by a beam shaper by a light modulator (60), and generally consists of one to two sheets.
光调制器(60)是指将入射的光线进行选择性通过、阻断或改变光径来形成影像图片的元件。光调制器(60)的典型实例有数字微镜器件(Digital
Micromirror Device,简称“DMD”)、液晶显示(Liquid Crystal Display,简称“LCD”)元件、硅基液晶(Liquid
Crystal On Silicon,简称“LCOS”)等等。The light modulator (60) refers to an element that selectively passes incident light, blocks or changes the optical path to form an image. A typical example of a light modulator (60) is a digital micromirror device (Digital
Micromirror Device ("DMD"), Liquid Crystal Display ("LCD") components, liquid crystal on silicon (Liquid)
Crystal On Silicon, referred to as "LCOS" and so on.
DMD是用在数字光处理(Digital Light
Processing,简称“DLP”)投影机的元件,它利用场时序(field
sequential)的驱动方式,使用与像素数量一样多的矩阵形态排列的数码镜(DIGITAL
MIRROR)。DLP是指从光源照射出的光用数码镜来调节光径,并用隔板反射来达到渐变(Gradation)或形成图象的投影仪。DMD is used in digital light processing (Digital Light
Processing, referred to as "DLP"), which uses the field timing (field)
Sequential), using a digital mirror arranged in the same number of pixels as the number of pixels (DIGITAL
MIRROR). DLP refers to a projector that uses light from a light source to adjust the optical path with a digital mirror and reflects it with a spacer to achieve Gradation or image formation.
液晶显示元件(LCD)是指选择性地开/关液晶来形成图象的元件。使用LCD元件的投影机中,有直视型(direct-view)、投射型以及反射型。直视型投影是液晶显示元件后面的背景光通过LCD面板形成图象并可以直接观察的方式;投射型投影是将通过液晶显示元件形成的图象利用投射透镜放大后投射到屏幕,观察从屏幕反射的图象的方式;反射型与投射型的结构基本相同,区别之处在于,反射型在LCD下面基板上设有反射膜,反射的光线被放大投射到屏幕上。A liquid crystal display element (LCD) refers to an element that selectively turns on/off a liquid crystal to form an image. Among the projectors using LCD elements, there are direct-view, projection, and reflection types. The direct-view projection is a method in which the background light behind the liquid crystal display element forms an image through the LCD panel and can be directly observed; the projection type projection is to enlarge an image formed by the liquid crystal display element by using a projection lens and project it onto the screen, and observe the slave screen. The way of reflecting the image; the reflective type is basically the same as the projected type, except that the reflective type is provided with a reflective film on the substrate under the LCD, and the reflected light is amplified and projected onto the screen.
LCOS属于反射型液晶显示,它将以往液晶显示端的两面基板中的下方基板由透明的玻璃改为硅基板,从而用反射型方式运作。LCOS is a reflective liquid crystal display, which converts the lower substrate of the two-sided substrate of the conventional liquid crystal display end from a transparent glass to a silicon substrate, thereby operating in a reflective manner.
偏振分光镜(80)是起到将入射光传递到光调制器(60)的作用的光学元件,其玻璃材质的六面体内,偏光分离膜以对角线分布,是反射型光学引擎所必须的一个光学元件。The polarization beam splitter (80) is an optical element that functions to transmit incident light to the light modulator (60). The hexahedron of the glass material and the polarization separation film are distributed diagonally, which is necessary for the reflective optical engine. An optical component.
入射光碰到偏振分光镜的偏光分离膜,S偏光被偏光分离膜反射到光调制器,P偏光透射过偏振分光镜被废弃。所有光源部(10)发出的光,在光路上的某一点要转换(Conversion)成线平行状态,才能维持光效率。但是激光光源的输出的光中偏光比达到数百比一,不需要转换线平行的光学部件,所以非常适用于微型投影机的光源。The incident light hits the polarization separation film of the polarization beam splitter, the S polarization is reflected by the polarization separation film to the light modulator, and the P polarization is transmitted through the polarization beam splitter and discarded. The light emitted by all the light source sections (10) is converted to a line parallel state at a certain point on the optical path to maintain the light efficiency. However, the output of the laser light source has a polarization ratio of several hundred to one, and does not require an optical component in which the conversion line is parallel, so it is very suitable for a light source of a micro projector.
这样经过偏光分离膜反射的S偏光通过光调制器形成影像的过程中转换为P偏光,转换为P偏光的影像光再次入射到偏振分光镜(80),碰到偏光分离膜。这回的影像光全是P偏光,所以透过偏光分离膜入射到投射透镜(70)。In this way, the S-polarized light reflected by the polarization separation film is converted into P-polarized light during formation of an image by the light modulator, and the image light converted into P-polarized light is again incident on the polarization beam splitter (80) and hits the polarization separation film. The image light of this time is all P-polarized, so it is incident on the projection lens (70) through the polarization separation film.
投射透镜(70)由多个透镜构成,将由光调制器(60)形成的图象向屏幕(图中未标识)上放大投射。The projection lens (70) is composed of a plurality of lenses, and an image formed by the light modulator (60) is enlarged and projected onto a screen (not shown).
上面描述的是反射型的光学引擎,本发明的技术方案也适用于透射型的光学引擎。透射型的光学引擎的结构与反射型的差不多,区别主要是没有偏振分光镜(80),此外,物镜(40)、光调制器(60)和投射透镜(70)的光路为同一直线。Described above is a reflective optical engine, and the technical solution of the present invention is also applicable to a transmissive optical engine. The structure of the transmissive optical engine is similar to that of the reflective type, the main difference being that there is no polarization beam splitter (80), and the optical paths of the objective lens (40), the light modulator (60) and the projection lens (70) are the same straight line.
图2是上述微型投影机中R/G/B三色激光驱动原理的简略图。微型投影机的光学引擎为了小型化,要用一个光调制器体现彩色影像。利用场时序(field
sequential)的驱动方式的液晶显示装置(LCD)是符合此目的光调制器。这样的场时序是指把时间表划分为3等分,在各自的时间上把对应三原色的绿,红,蓝影像依次显示的方式。人眼对影像会有残留现象,把影像以一定速度以上显示时,就会认为是连续画面。电影或动画就是利用该原理。色彩影像也是一样,快速显示R/G/B三原色时,因残影效果,观看者会认为是三原色混合色的白色。同样三原色的光量不同时可以调整出多种颜色,所以可以调整三原色的相对光量来达到显示我们所要色彩的目的。2 is a schematic view showing the principle of R/G/B three-color laser driving in the above-described pico projector. In order to miniaturize the optical engine of the pico projector, a light modulator is used to represent the color image. Use field timing (field
A sequential liquid crystal display device (LCD) is a light modulator that conforms to this purpose. Such a field timing refers to a method in which the time zone is divided into three equal parts, and the green, red, and blue images corresponding to the three primary colors are sequentially displayed at respective times. The human eye will have a residual image, and when the image is displayed at a certain speed or higher, it will be regarded as a continuous picture. Movies or animations use this principle. The color image is the same. When the R/G/B primary colors are quickly displayed, the viewer will consider the three primary colors mixed white due to the afterimage effect. Similarly, when the amount of light of the three primary colors is different, a plurality of colors can be adjusted, so that the relative amounts of the three primary colors can be adjusted to achieve the purpose of displaying the desired color.
场时序驱动是把60Hz的影像画面重新3等分。把一个影像画面根据各像素制作三原色光量对应的R/G/B分影像,然后把上述的分影像以180Hz驱动。根据上述的180Hz的分影像同步入射R/G/B光,就可以得到60Hz的彩色影像。图2说明的是上述根据180Hz分影像驱动R/G/B三个光源的驱动信号。The field timing drive is to re-divide the 60 Hz image frame by three equal parts. An R/G/B sub-image corresponding to the amount of light of the three primary colors is generated for each video image, and then the above-described sub-image is driven at 180 Hz. According to the above-mentioned 180 Hz sub-image synchronously incident R/G/B light, a 60 Hz color image can be obtained. FIG. 2 illustrates the above-described driving signals for driving the three R/G/B light sources according to the 180 Hz sub-image.
如图2所示,R光源信号是180Hz,有个On
time区间。各光源之间的区间用于往光调制器传输各像素光量数据,每帧中有3个这种区间,其和是全体负载的10%左右。As shown in Figure 2, the R source signal is 180Hz, there is an On
Time interval. The interval between the light sources is used to transmit the light quantity data of each pixel to the light modulator, and there are three such intervals in each frame, and the sum is about 10% of the total load.
控制好各光源的On
time,协同光调制器对应的时间信号,用一定的光能量反复进行180Hz的开/关动作。Control the On of each light source
Time, in conjunction with the time signal corresponding to the light modulator, repeats the 180 Hz on/off action with a certain amount of light energy.
本发明实施方式对这种简单的光源驱动作了改进,以减少激光的连贯特性。Embodiments of the present invention improve upon such simple light source driving to reduce the coherence characteristics of the laser.
激光是同一波长,同一振幅,同一相位光的集合体,有着很强的连贯特性。即使通过光束整形器整形和扩大成面光源,还是会产生随机性的干涉影像点,这个干涉影像点体现为斑点,叫做散斑。本发明的发明人认为存在以下关系:The laser is a collection of the same wavelength, the same amplitude, and the same phase of light, with strong coherence. Even if the beam shaper is used to shape and expand the surface light source, random interference image points will be generated. This interference image point is reflected as a speckle, called speckle. The inventors of the present invention believe that the following relationship exists:
随机性(Randomness)=波长的可变×相位的可变×入射角的可变Randomness = variable wavelength × variable phase × variable angle of incidence
相应于上面的公式,有以下3种代表性方法可以减少入射光的连贯特性。Corresponding to the above formula, there are three representative methods to reduce the coherence of incident light.
方法一是入射角可变。The first method is that the incident angle is variable.
图1的漫射体(20)就是入射角可变的方法。但是光用漫射体(20)是不能完全消灭散斑,还需配合以其它方法。The diffuser (20) of Figure 1 is a method of variable angle of incidence. However, the light diffuser (20) cannot completely eliminate the speckle, and it is necessary to cooperate with other methods.
方法二是相位可变。The second method is that the phase is variable.
相位可变方法是在偏光上给于变化,在光调制器前端使用是存在困难。The phase-variable method is to give a change in the polarization, and it is difficult to use it at the front end of the optical modulator.
方法三是波长可变。The third method is that the wavelength is variable.
波长可变可以做为漫射体(20)以外的一种重要手段。Variable wavelengths can be used as an important means other than diffusers (20).
图3是适用本发明的一个案例中对光源驱动进行改进的示意图。Figure 3 is a schematic illustration of an improvement in light source driving in a case in which the present invention is applied.
激光二极管发出的虽然是单一波长的光,不过在两种情况下可以让波长有变化。The laser diode emits light of a single wavelength, but in both cases the wavelength can be varied.
第一种是温度的变化。激光二极管的工作温度变化时发出的光的波长会渐渐改变,这样的改变范围大概是0.25nm/ C°左右。在-10 C°~+10
C°范围内连续变动的话波长也会任意持续变化。The first is the change in temperature. The wavelength of the light emitted by the laser diode changes gradually as the operating temperature changes. This range of change is about 0.25 nm / C °. At -10 C°~+10
The wavelength will continue to change arbitrarily if the C° range continuously changes.
要控制工作温度就要增加改变激光二极管温度的装置,这会有使光学引擎体积会变大的缺点。To control the operating temperature, it is necessary to increase the temperature of the laser diode, which has the disadvantage that the optical engine will become bulky.
第二种是将如图3所示光源的开启时间(On
Time)分成多个区间,调制成高速负载。图纸上为了说明方便分为近10个区间,但实际上是3Khz以上的高速调制。特别是进行300Mhz的高速调制时,波长的波动引起的散斑减少效果明显。这是因为激光二极管特有的共振现象,使存在于激光二极管活性领域的电荷密度的大小波动变大,这使共振机内的曲折率产生变化引发波长的波动。
The second is to turn on the light source as shown in Figure 3.
Time) is divided into a plurality of intervals and modulated into a high speed load. The drawing is divided into nearly 10 sections for the convenience of explanation, but it is actually a high-speed modulation of 3Khz or more. In particular, when the high-speed modulation of 300 Mhz is performed, the speckle reduction effect caused by the fluctuation of the wavelength is remarkable. This is because the resonance phenomenon unique to the laser diode causes the fluctuation in the magnitude of the charge density existing in the active field of the laser diode to be large, which causes the variation in the tortuosity in the resonator to cause fluctuations in the wavelength.
调制驱动时图3上把输入负载调整到一半大小,高速调制时输入负载的最小值可以是最大值至0之间的任意值。In the case of modulation drive, the input load is adjusted to half the size in Figure 3. The minimum value of the input load during high-speed modulation can be any value between the maximum value and zero.
红色和蓝色激光可以调制成以数百Mhz变化的负载,但绿色光不可以。是因为绿色光是由叫二极管泵浦模块(Diode Pumped
Module,简称“DPM”)的光学元件发出的。Red and blue lasers can be modulated into loads that vary by hundreds of Mhz, but green light is not. Because the green light is called the diode pump module (Diode Pumped)
The optical component of the Module, referred to as "DPM" for short.
因为到目前为止还没有开发出固体的绿色激光器,所以绿色激光通过二次谐波产生(Second
Harmonic Generation,简称“SHG”)把长波长的红外激光(Infrared Laser)倍频(Frequency
Doubling)转换为绿色波长来使用。一般利用DPM(90)这种光学元件进行倍频,其构造在图4中有简单介绍。Since a solid green laser has not been developed so far, the green laser is generated by the second harmonic (Second)
Harmonic Generation ("SHG" for short) multi-wavelength infrared laser (Infrared Laser) multiplier (Frequency
Doubling) is converted to a green wavelength to use. Frequency multiplication is generally performed using an optical component such as DPM (90), the construction of which is briefly described in FIG.
红外激光(100)发出的800nm左右的波长光通过DPM(90)转换为532nm的绿色光。这样的DPM(Diode Pumped
Module)由Nd:YVO4(110,添加了Nd的钒酸钇)和KTP(120)构成。KTP(120)是KTiOPO4(Potassium Titanyl
Phosphate Crystals磷酸钛氧钾晶体)是属于非线性光学元件,多用于激光的倍频上。The wavelength of about 800 nm emitted by the infrared laser (100) is converted into green light of 532 nm by DPM (90). Such DPM (Diode Pumped
Module) consists of Nd:YVO4 (110, Nd-doped yttrium vanadate) and KTP (120). KTP (120) is KTiOPO4 (Potassium Titanyl)
Phosphate Crystals is a nonlinear optical component that is used in the frequency doubling of lasers.
利用Nd:YVO4(110)把808nm的红外激光(100)转换成1064nm的长波长的光,再把1064nm的长波长激光通过非线性元件KTP(120)倍频到532nm的绿色激光。The 808 nm infrared laser (100) is converted into a long-wavelength light of 1064 nm by Nd:YVO4 (110), and the long-wavelength laser of 1064 nm is multiplied by a non-linear element KTP (120) to a green laser of 532 nm.
上述DPM(90)不能适应数百Mhz的高速调制,所以要改为数khz程度。在本发明的一个优先实例中,上述的绿色光的光调制可以到2000KHz。当然也可以调制成其它的频率,如1500Hz,2500Hz等等,不过效果会差一些。The above DPM (90) cannot accommodate the high-speed modulation of hundreds of Mhz, so it should be changed to a few degrees of khz. In a preferred embodiment of the invention, the light modulation of the green light described above can be up to 2000 KHz. Of course, it can also be modulated into other frequencies, such as 1500Hz, 2500Hz, etc., but the effect will be worse.
上述DPM(90)除了在前面说的通过驱动调制波长波动减少散斑效果外还有一个优点。The above DPM (90) has an advantage in addition to the speckle reduction effect by driving modulation wavelength fluctuations as previously described.
图5是DPM(90)针对输入负载的工作特性的示意图。图5a是输入负载的现有驱动方法的输出图。图5b是把输入负载高速调制时的输出图。把绿色光源调制到数Khz反复开/关情况下整个负载期间的光输出量反而增加了。这是因为DPM的输出能力在负载量适量增加的时候有逐渐衰减的特性。所以负载间off区间增加但光输出量却在增加。Figure 5 is a schematic illustration of the operational characteristics of DPM (90) for an input load. Figure 5a is an output diagram of an existing drive method for inputting a load. Fig. 5b is an output diagram when the input load is modulated at a high speed. When the green light source is modulated to a number Khz repeatedly on/off, the light output during the entire load is increased. This is because the output capability of the DPM has a gradual attenuation characteristic when the load amount is increased. Therefore, the off interval between loads increases but the light output increases.
图5中对形成绿色光源的红外激光的输入负载以开/关方式调制,也就是说输入负载变化的最小值是0,本发明的实施方式并不限于这种调制方式,输入负载变化的最小值其实可以是0至最大值之间的任一个值。In Fig. 5, the input load of the infrared laser forming the green light source is modulated in an on/off manner, that is, the minimum value of the input load change is 0, and the embodiment of the present invention is not limited to this modulation mode, and the input load variation is minimal. The value can actually be any value between 0 and the maximum.
本实施方式中,光源的调制可由调制驱动单元完成,该单元用于将光源在开启时间期间的输入负载调制成以一千赫兹以上频率变化的负载。可以理解,调制驱动单元是一个逻辑单元,可以以独立的物理单元实现,也可以是一个物理单元的一部分,还可以以多个物理单元的组合实现,调制驱动单元本身的物理实现方式并不是最重要的,其所实现的功能是才解决本发明所提出的技术问题的一个关键。In this embodiment, the modulation of the light source can be accomplished by a modulation drive unit that modulates the input load of the light source during the on time to a load that varies at a frequency above one kilohertz. It can be understood that the modulation driving unit is a logic unit, which can be implemented as a separate physical unit, or can be part of one physical unit, or can be implemented by a combination of multiple physical units. The physical implementation of the modulation driving unit itself is not the most Importantly, the functions it implements are a key to solving the technical problems presented by the present invention.
可见,在激光光源的On
time驱动时进行数KHz以上的调制驱动,可以减少激光的连贯特性,削弱散斑现象。特别在绿色光的情况下,除了可以减少散斑现象外还可以增大光输出效率。Visible in the laser light source On
When the time is driven, the modulation drive of several KHz or more is performed, which can reduce the coherence characteristics of the laser and weaken the speckle phenomenon. Especially in the case of green light, in addition to reducing the speckle phenomenon, the light output efficiency can be increased.
除了通过对激光光源的高频调制和引入漫射体可以削弱激光散斑外,还可以引入用于振动光束整形器的元件,通过振动光束整形器进一步削弱激光散斑。In addition to weakening the laser speckle by high frequency modulation of the laser source and introduction of the diffuser, elements for the vibrating beam shaper can be introduced, which are further attenuated by the vibrating beam shaper.
上述实施方式是针对三个激光光源的,但本发明的技术方案并不限于三个激光光源的光学引擎,也可以是一个、二个或更多个激光光源,还可以是激光光源和发光二级管(Light
Emitting
Diode,简称“LED”)光源组成的混合光源,例如一个红色激光光源,一个由红外激光光源经倍频生成的绿色激光,还有一个蓝色的LED光源。The above embodiments are directed to three laser light sources, but the technical solution of the present invention is not limited to the optical engines of three laser light sources, and may be one, two or more laser light sources, or may be laser light sources and light emitting diodes. Level tube (Light
Emitting
Diode, referred to as "LED"), is a hybrid light source, such as a red laser source, a green laser generated by an infrared laser source, and a blue LED source.
虽然通过参照本发明的某些优选实施方式,已经对本发明进行了图示和描述,但本领域的普通技术人员应该明白,可以在形式上和细节上对其作各种改变,而不偏离本发明的精神和范围。Although the invention has been illustrated and described with reference to the preferred embodiments of the present invention, it will be understood The spirit and scope of the invention.