TW202225637A

TW202225637A - Laser confocal measurement system and light control module thereof

Info

Publication number: TW202225637A
Application number: TW109146975A
Authority: TW
Inventors: 蔡政廷; 邱國智
Original assignee: 致茂電子股份有限公司
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2022-07-01
Also published as: TWI761011B

Abstract

The present application discloses a laser confocal measurement system and light control module thereof, which are used to control on an optical path in/out of the MEMS mirror module. The light control module receives a laser beam having a first polarization state and receives a measured light from an object to be measured and having a second polarization state. The first polarization state is orthogonal to the second polarization state. The light control module makes the laser beam emitted and directed to the MEMS mirror module to be circularly polarized light or elliptically polarized light, and converts the laser beam reflected from the MEMS mirror module into linearly polarized light. With the reflection mechanism of the MEMS mirror module and the conversion between different polarization types, the light incident on the MEMS mirror module can be incident at 0 degrees and the formed scanning light has the characteristics of low distortion and low light decay.

Description

雷射共焦量測系統及雷射共焦量測系統的光控制模組Laser confocal measurement system and optical control module of laser confocal measurement system

本發明係關於一種量測系統及光控制模組，特別是關於一種基於雷測共焦量測技術的雷射共焦量測系統及雷射共焦量測系統的光控制模組。The present invention relates to a measurement system and an optical control module, in particular to a laser confocal measurement system based on the laser measurement confocal measurement technology and an optical control module of the laser confocal measurement system.

雷射共焦系統(又稱雷射共軛焦系統)係為一種可用來量測物體表面形貌的技術，其精度範圍約為1~100奈米的等級，可符合高精度量測的目的。The laser confocal system (also known as the laser confocal system) is a technology that can be used to measure the surface topography of an object. Its accuracy ranges from 1 to 100 nm, which can meet the purpose of high-precision measurement. .

習知的雷射共焦系統中，是藉由***控在兩個軸向上產生旋轉的微機電反射鏡來達到二維的掃瞄。一般而言，微機電反射鏡採用45度角之傾斜配置，以使反射光可被90度轉向而反射至待測面上，然而，這樣的配置會導致較嚴重的扇形失真(distortion)，在掃描精度逐漸提高下，這樣的傾斜配置方式難以符合掃描需求。In conventional confocal laser systems, two-dimensional scanning is achieved by manipulating MEMS mirrors that rotate in two axial directions. Generally speaking, the MEMS mirror adopts an inclined configuration of 45 degrees, so that the reflected light can be turned by 90 degrees and reflected to the surface to be measured. However, such a configuration will lead to serious sector distortion. With the gradual improvement of scanning accuracy, it is difficult for such an inclined configuration to meet the scanning requirements.

另一種方式是，在微機電反射鏡前額外配置一個分光鏡(Beam splitter)，雷射光束在入射微機電反射鏡前，先入射至分光鏡，經由分光鏡改變光路徑，讓入射該微機電反射鏡的光線是來自該分光鏡的反射光。而自該微機電反射鏡所反射的光線，則再經由該分光鏡的透射，朝待測面的方向入射。藉此，入射該微機電反射鏡的入射角可以小於前述舉例的傾斜配置方式，然而，由於分光鏡具有50%反射光線及50%透射光線的特性，因此光每通過一次分光鏡即會損失50%的能量，導致入射光到達待測面時衰減了75%。基於雷測共焦量測技術，自待測面發出的光線會再經過相同的反向路徑射回，因此，從待測物反射的光線沿原光路鏡返回至光電倍增管(photomultiplier tube, PMT)後，用光效率僅剩下原始出射光的6~7%。Another way is to configure an additional beam splitter in front of the MEMS mirror. Before entering the MEMS mirror, the laser beam first enters the beam splitter, and the beam splitter changes the light path so that the incident MEMS mirror The light from the reflector is the reflected light from the beam splitter. The light reflected from the MEMS mirror is then transmitted through the beam splitter and is incident in the direction of the surface to be measured. In this way, the incident angle of the MEMS mirror can be smaller than the above-mentioned inclined configuration. However, since the beam splitter has the characteristics of 50% reflected light and 50% transmitted light, the light will lose 50% each time it passes through the beam splitter. % of the energy, causing the incident light to be attenuated by 75% when it reaches the surface to be measured. Based on the confocal measurement technology of lightning measurement, the light emitted from the surface to be measured will return through the same reverse path. Therefore, the light reflected from the object to be measured will return to the photomultiplier tube (PMT) along the original optical path mirror. ), the light efficiency is only 6~7% of the original outgoing light.

據此，習知的雷射共焦系統存在失真嚴重或用光效率不佳的問題。Accordingly, the conventional laser confocal system has problems of serious distortion or poor light utilization efficiency.

本發明之一目的在於解決雷射共焦系統中的影像失真問題。One objective of the present invention is to solve the problem of image distortion in a laser confocal system.

本發明之另一目的在於提高雷射共焦系統中的用光效率。Another object of the present invention is to improve the light efficiency in the laser confocal system.

為達上述目的及其他目的，本發明提出一種雷射共焦量測系統的光控制模組，用於在一微機電反射鏡模組的進/出光路徑上進行控制，並用於接收第一偏振態的雷射光束，以及用於接收來自待測物且為第二偏振態的量測光以提供至該微機電反射鏡模組，其特徵在於：該光控制模組係用以使出射且射向該微機電反射鏡模組的該雷射光束係為圓形偏振光或橢圓偏振光，該光控制模組並用以使反射自該微機電反射鏡模組的該雷射光束轉換為線性偏振光，該第一偏振態係正交於該第二偏振態。In order to achieve the above purpose and other purposes, the present invention provides a light control module of a laser confocal measurement system, which is used to control the in/out light path of a micro-electromechanical mirror module, and is used to receive the first polarization A laser beam in a state of being, and for receiving the measurement light in the second polarization state from the object to be measured to provide to the MEMS mirror module, characterized in that: the light control module is used to make the outgoing and The laser beam directed to the MEMS mirror module is circularly polarized light or elliptically polarized light, and the light control module is used to convert the laser beam reflected from the MEMS mirror module to linear For polarized light, the first polarization state is orthogonal to the second polarization state.

於本發明之一實施例中，該光控制模組包含：極化分光器及1/4波板。極化分光器係反射該第一偏振態的入射光，以及透射該第二偏振態的入射光。1/4波板被配置於該極化分光器與該微機電反射鏡模組之間。其中，自該極化分光器出射且遠離該微機電反射鏡模組的該雷射光束係為該第二偏振態，自該極化分光器出射且遠離該微機電反射鏡模組的該量測光係為該第一偏振態。In an embodiment of the present invention, the light control module includes: a polarization beam splitter and a quarter wave plate. The polarization beam splitter reflects the incident light of the first polarization state and transmits the incident light of the second polarization state. A quarter wave plate is disposed between the polarization beam splitter and the MEMS mirror module. Wherein, the laser beam emitted from the polarization beam splitter and away from the MEMS mirror module is in the second polarization state, and the amount of the laser beam emitted from the polarization beam splitter and away from the MEMS mirror module The photometric system is the first polarization state.

於本發明之一實施例中，可更包含一極化器，該極化器配置於該極化分光器接收該第一偏振態之該雷射光束的這一側，該極化器係使通過之光線轉換為該第一偏振態的光線。In one embodiment of the present invention, a polarizer may be further included, and the polarizer is disposed on the side of the polarization beam splitter that receives the laser beam of the first polarization state, and the polarizer makes The passing light is converted to light of the first polarization state.

於本發明之一實施例中，該第一偏振態為S偏振，該第二偏振態為P偏振。In an embodiment of the present invention, the first polarization state is S polarization, and the second polarization state is P polarization.

於本發明之一實施例中，自該極化分光器出射且射向該微機電反射鏡模組之該雷射光束的線偏振方向係與該1/4波板之光軸間具有±45度的夾角。In an embodiment of the present invention, the linear polarization direction of the laser beam emitted from the polarization beam splitter and directed to the MEMS mirror module is ±45° from the optical axis of the quarter wave plate. angle of degrees.

為達上述目的及其他目的，本發明復提出一種雷射共焦量測系統，用於在第一光路徑上將雷射光束提供至待測物，並接收來自該待測物的量測光以使該量測光被導引至量測裝置，該雷射共焦量測系統包含：分光模組、微機電反射鏡模組、聚焦模組、及光控制模組。分光模組配置為透射該雷射光束，以及反射該量測光至第二路徑，使該量測光入射至該量測裝置。聚焦模組配置為透射作為掃描光束的該雷射光束，以及透射來自該待測物的該量測光。光控制模組配置為調整來自該分光模組的該雷射光束以入射至該微機電反射鏡模組，及接收來自該微機電反射鏡模組所反射的該雷射光束以入射至該聚焦模組，該光控制模組係使出射且射向該微機電反射鏡模組的該雷射光束係為圓形偏振光或橢圓偏振光，以及使反射自該微機電反射鏡模組的該雷射光束轉換為線性偏振光，以及使出射且遠離該微機電反射鏡模組的該量測光係為第一偏振態的線性偏振光，以及使出射且遠離該微機電反射鏡模組的該雷射光束係為第二偏振態的線性偏振光，該第一偏振態係正交於該第二偏振態。In order to achieve the above object and other objects, the present invention further proposes a laser confocal measurement system for providing a laser beam to an object to be measured on a first optical path, and receiving measurement light from the object to be measured In order to guide the measurement light to the measurement device, the laser confocal measurement system includes: a beam splitting module, a MEMS mirror module, a focusing module, and a light control module. The beam splitting module is configured to transmit the laser beam and reflect the measurement light to the second path, so that the measurement light is incident on the measurement device. The focusing module is configured to transmit the laser beam as a scanning beam and transmit the measurement light from the object to be measured. The light control module is configured to adjust the laser beam from the beam splitting module to be incident on the MEMS mirror module, and to receive the laser beam reflected from the MEMS mirror module to be incident on the focus A module, the light control module makes the laser beam emitted from the MEMS mirror module be circularly polarized light or elliptically polarized light, and makes the laser beam reflected from the MEMS mirror module The laser beam is converted into linearly polarized light, and the measuring light that exits and is far away from the MEMS mirror module is linearly polarized light of the first polarization state, and the light that exits and is far away from the MEMS mirror module is linearly polarized light of the first polarization state. The laser beam is linearly polarized light of a second polarization state, and the first polarization state is orthogonal to the second polarization state.

據此，藉由微機電反射鏡模組的反射機制搭配相異偏振光型態間的轉換，可讓入射至微機電反射鏡模組的光線在呈0度入射的情況下，不會有過多的用光效率的損失，進而使所形成的掃瞄光具有低失真與低光衰的特性。Accordingly, through the reflection mechanism of the MEMS mirror module and the conversion between different polarized light types, the light incident on the MEMS mirror module can be prevented from being too much under the condition of 0 degree incidence. Therefore, the formed scanning light has the characteristics of low distortion and low light attenuation.

為充分瞭解本發明之目的、特徵及功效，茲藉由下述具體之實施例，並配合所附之圖式，對本發明做一詳細說明，說明如後：In order to fully understand the purpose, features and effects of the present invention, hereby, the present invention is described in detail by the following specific embodiments and in conjunction with the accompanying drawings, and the description is as follows:

於本文中，所描述之用語「一」或「一個」來描述單元、部件、結構、裝置、模組、系統、部位或區域等。此舉只是為了方便說明，並且對本發明之範疇提供一般性的意義。因此，除非很明顯地另指他意，否則此種描述應理解為包括一個或至少一個，且單數也同時包括複數。As used herein, the terms "a" or "an" are described to describe a unit, component, structure, device, module, system, portion or region, or the like. This is done only for convenience of description and to provide a general sense of the scope of the invention. Accordingly, unless it is clear that it is meant otherwise, such descriptions should be read to include one or at least one, and the singular also includes the plural.

於本文中，所描述之用語「包含、包括、具有」或其他任何類似用語意係非僅限於本文所列出的此等要件而已，而是可包括未明確列出但卻是所述單元、部件、結構、裝置、模組、系統、部位或區域通常固有的其他要件。In this text, the terms "comprising, including, having" or any other similar terms described are not meant to be limited to the elements listed herein, but may include elements that are not explicitly listed but are the stated elements, Other elements usually inherent in a component, structure, device, module, system, location or area.

於本文中，所描述之「第一」或「第二」等類似序數之詞語，係用以區分或指關聯於相同或類似的元件或結構、部位或區域，且不必然隱含此等元件、結構、部位或區域在空間上的順序。應了解的是，在某些情況或配置下，序數詞語係可交換使用而不影響本發明之實施。In this document, words like "first" or "second" described in ordinal numbers are used to distinguish or refer to the same or similar elements or structures, parts or regions, and do not necessarily imply such elements , the spatial order of structures, parts or regions. It should be understood that under certain circumstances or configurations, ordinal words may be used interchangeably without affecting the practice of the invention.

請參照圖1，其係為本發明一實施例之雷射共焦量測系統的示意圖。雷射共焦量測系統係將雷射光源裝置100提供的雷射光束經由光束控制後，提供至聚焦模組500，進而照射置放在載台700上的待測物。Please refer to FIG. 1 , which is a schematic diagram of a laser confocal measurement system according to an embodiment of the present invention. The laser confocal measurement system supplies the laser beam provided by the laser light source device 100 to the focusing module 500 after beam control, and then illuminates the object to be measured placed on the stage 700 .

微機電反射鏡模組400可為一種二維微機電反射鏡(2D MEMS Mirror)，藉由數位控制的微鏡來使光線反射至所需的路徑。據此，經由光控制模組300及微機電反射鏡模組400的協同運作，可形成對待測物表面上一定區域範圍內的掃描動作。作為掃描光束的雷射光束在照射待測物後，自待測物表面反射或發光的光線係為量測光。於後述實施例中，為便於區分，係稱未入射至待測物的光束為雷射光束，並將自待測物表面返回的光線統一稱為量測光。The MEMS mirror module 400 can be a two-dimensional MEMS mirror (2D MEMS mirror), and the light is reflected to a desired path by a digitally controlled micro mirror. Accordingly, through the cooperative operation of the light control module 300 and the MEMS mirror module 400, a scanning action within a certain area on the surface of the object to be measured can be formed. After the laser beam as the scanning beam irradiates the object to be measured, the light reflected or emitted from the surface of the object to be measured is the measurement light. In the following embodiments, for the convenience of distinction, the light beam not incident on the object to be measured is referred to as a laser beam, and the light returning from the surface of the object to be measured is collectively referred to as measurement light.

自待測物表面返回的光線會再次入射光控制模組300及微機電反射鏡模組400，再經由分光模組200將量測光改變至第二光路徑。其中，自雷射光源裝置100出發之雷射光束所經過的路徑以及量測光返回至分光模組200的路徑係定義為第一光路徑，自分光模組200至量測裝置600的光電倍增管630 (Photomultiplier Tube, PMT)的路徑係定義為第二光路徑。量測裝置600包含：聚焦透鏡610、針孔裝置620 (Pinhole)、及光電倍增管630、The light returning from the surface of the object to be measured will be incident on the light control module 300 and the MEMS mirror module 400 again, and then the measurement light will be changed to the second light path through the light splitting module 200 . The path of the laser beam from the laser light source device 100 and the path of the measurement light returning to the beam splitting module 200 are defined as the first optical path, and the photomultiplier from the beam splitting module 200 to the measuring device 600 is defined as the first optical path. The path of the tube 630 (Photomultiplier Tube, PMT) is defined as the second light path. The measuring device 600 includes: a focusing lens 610, a pinhole device 620, and a photomultiplier tube 630,

後續藉由聚焦透鏡610使量測光匯聚，並於焦點處設置針孔裝置620，將非聚焦面的光線排除在外，最後令聚焦面的量測光入射至光電倍增管630。自待測物表面返回的光線的出發點若是處於聚焦模組500焦點上，那麼返回至聚焦透鏡610之焦點處的針孔裝置620時，就同樣可通過針孔裝置620，其餘光線則會被針孔裝置620所阻擋，進而形成共聚焦的量測。Subsequently, the measuring light is concentrated by the focusing lens 610 , and a pinhole device 620 is arranged at the focal point to exclude the light on the non-focusing surface, and finally the measuring light on the focusing surface is incident on the photomultiplier tube 630 . If the starting point of the light returning from the surface of the object to be measured is at the focus of the focusing module 500, then when it returns to the pinhole device 620 at the focus of the focusing lens 610, it can also pass through the pinhole device 620, and the rest of the light will be captured by the pinhole device 620. Aperture device 620 is blocked, resulting in a confocal measurement.

雷射光源裝置100例如可透過雷射源110、導引雷射光的光纖120及使雷射光形成平行光束的準直透鏡130(Collimator lens)來形成入射該分光模組200的該雷射光束。該分光模組200可令該雷射光束透射，以及可令前述之量測光反射。The laser light source device 100 can, for example, form the laser beam incident on the beam splitting module 200 through the laser source 110 , the optical fiber 120 for guiding the laser light, and the collimator lens 130 for forming the laser light into a parallel beam. The beam splitting module 200 can transmit the laser beam, and can reflect the aforementioned measurement light.

聚焦模組500藉由可進一步確保雷射光束之平行化或同時擴大平行光之光束的掃描透鏡511(Scan lens)及鏡筒透鏡512(Tube lens)的組合，提高入射至待測物的光束品質。分光裝置520在圖1中係基於光路的安排而使用，於其他實施態樣下，亦可能無須使用該分光裝置520或是替換為反射鏡。分光裝置520在圖1中被繪示為作為反射鏡使用，也可利用分光裝置520透射的特性，將量測光在分光裝置520所產生的透射分量(圖未示)作為觀察使用，用以進行初步定位來對準待測物。物鏡530用於將雷射光束聚焦至載台700，同時可接收自待測物表面之所反射或發出的量測光，使該量測光透射，進而可沿著原路徑返回該分光模組200。The focusing module 500 improves the beam incident on the object to be measured by the combination of the scan lens 511 (Scan lens) and the tube lens 512 (Tube lens) which can further ensure the parallelization of the laser beam or simultaneously expand the beam of the parallel light. quality. The light splitting device 520 is used based on the arrangement of the optical paths in FIG. 1 . In other implementations, the light splitting device 520 may not be used or may be replaced with a mirror. The spectroscopic device 520 is shown as being used as a mirror in FIG. 1 , and the transmittance component (not shown) generated by the measuring light in the spectroscopic device 520 can also be used for observation by utilizing the transmission characteristics of the spectroscopic device 520 . Perform preliminary positioning to align the object to be tested. The objective lens 530 is used to focus the laser beam to the stage 700, and at the same time, it can receive the measurement light reflected or emitted from the surface of the object to be measured, so that the measurement light can be transmitted, and then can return to the spectroscopic module along the original path 200.

光控制模組300用於在微機電反射鏡模組400的進/出光路徑上進行控制。微機電反射鏡模組400的進光路徑與出光路徑係指在雷射共焦量測系統中，位於微機電反射鏡模組400前方一區段的光路徑，亦即入射至微機電反射鏡模組400的一段路徑與自微機電反射鏡模組400出射後的一段路徑。The light control module 300 is used to control the in/out light path of the MEMS mirror module 400 . The light input path and the light output path of the MEMS mirror module 400 refer to the light path located in a section in front of the MEMS mirror module 400 in the laser confocal measurement system, that is, the light path incident on the MEMS mirror A section of the path of the module 400 and a section of the path after being emitted from the MEMS mirror module 400 .

光控制模組300可用於接收來自雷射光源裝置100所提供之第一偏振態的雷射光束1S，以提供至微機電反射鏡模組400。以及，光控制模組300可用於接收來自待測物且為第二偏振態的量測光2P，以提供至微機電反射鏡模組400。實施例中所描述的第一偏振態與第二偏振態的光束係指光束之電磁波的偏振方向，第一偏振態與第二偏振態相垂直。其中第一偏振態可以是P偏振或S偏振，實施例中係以第一偏振態為S偏振來做為示例。The light control module 300 can be used for receiving the laser beam 1S of the first polarization state provided by the laser light source device 100 to provide the laser beam 1S to the MEMS mirror module 400 . And, the light control module 300 can be used to receive the measurement light 2P of the second polarization state from the object to be measured, and provide the measurement light 2P to the MEMS mirror module 400 . The light beams of the first polarization state and the second polarization state described in the embodiments refer to the polarization directions of the electromagnetic waves of the light beams, and the first polarization state and the second polarization state are perpendicular to each other. The first polarization state may be P polarization or S polarization. In the embodiment, the first polarization state is S polarization as an example.

光控制模組300可讓出射且射向該微機電反射鏡模組400的雷射光束形成為圓形偏振光或橢圓偏振光。此外，該光控制模組300並可讓自該微機電反射鏡模組400反射的雷射光束，在入射光控制模組300後，使其轉換為線性偏振光。The light control module 300 can make the laser beam emitted from the MEMS mirror module 400 to be circularly polarized light or elliptically polarized light. In addition, the light control module 300 can convert the laser beam reflected from the MEMS mirror module 400 into linearly polarized light after incident on the light control module 300 .

光控制模組300主要可包含：極化分光器310及1/4波板320。極化分光器310主要用來將入射的光束分成兩個極化方向互相正交的光束。1/4波板是一種雙折射材料。當入射之光束的極化方向與1/4波板的光軸(或稱晶體光軸)具有非0的一夾角時， 1/4波板可發揮出相位延遲的效果，進而調整光束的極化狀態。The light control module 300 may mainly include: a polarization beam splitter 310 and a quarter wave plate 320 . The polarization beam splitter 310 is mainly used to split the incident light beam into two light beams whose polarization directions are orthogonal to each other. A quarter wave plate is a birefringent material. When the polarization direction of the incident beam and the optical axis of the 1/4 wave plate (or the optical axis of the crystal) have a non-zero angle, the 1/4 wave plate can exert the effect of phase delay, and then adjust the polarization of the beam. state.

如圖1所示，極化分光器310反射第一偏振態的雷射光束1S，使雷射光束改變路徑而朝向1/4波板320入射。第一偏振態的雷射光束1S經過1/4波板320後，可成為圓形偏振光或橢圓偏振光。依圖1所示例者，第一偏振態的雷射光束1S經過1/4波板320後係成為右旋的圓偏振光1R(以微機電反射鏡模組400的觀察角度)。接著，再經微機電反射鏡模組400的反射後，再次入射1/4波板320。入射至1/4波板320時，以1/4波板320的觀察角度來說，係為左旋的圓偏振光1L入射。出射後的雷射光束改變為第二偏振態的雷射光束1P。極化分光器310透射第二偏振態的雷射光束1P，此雷射光束即成為照射至待測物上的掃描光。As shown in FIG. 1 , the polarization beam splitter 310 reflects the laser beam 1S of the first polarization state, so that the laser beam changes its path and is incident toward the quarter wave plate 320 . The laser beam 1S of the first polarization state can become circularly polarized light or elliptically polarized light after passing through the quarter wave plate 320 . According to the example shown in FIG. 1 , the laser beam 1S of the first polarization state becomes a right-handed circularly polarized light 1R after passing through the quarter wave plate 320 (at the viewing angle of the MEMS mirror module 400 ). Next, after being reflected by the MEMS mirror module 400 , the 1/4 wave plate 320 is incident again. When incident on the 1/4 wave plate 320 , in terms of the observation angle of the 1/4 wave plate 320 , the incident is a left-handed circularly polarized light 1L. The emitted laser beam is changed to a laser beam 1P of the second polarization state. The polarization beam splitter 310 transmits the laser beam 1P of the second polarization state, and the laser beam becomes the scanning light irradiated on the object to be measured.

如圖1所示，自待測物處所返回的量測光，可能同時有第一偏振態及第二偏振態，後續係僅對第二偏振態進行調整。第二偏振態的量測光2P進入極化分光器310後可被透射，進而入射1/4波板320。第二偏振態的量測光2P經過1/4波板320後可成為左旋的圓偏振光2L(以微機電反射鏡模組400的觀察角度)，經微機電反射鏡模組400的反射後，再次入射1/4波板320。入射至1/4波板320時，以1/4波板320的觀察角度來說，係為右旋的圓偏振光2R入射，出射後的雷射光束則改變為第一偏振態的量測光2S。極化分光器310反射第一偏振態的量測光2S，此量測光後續透過分光模組200可被反射至第二路徑，進而入射量測裝置600。As shown in FIG. 1 , the measurement light returned from the object to be measured may have a first polarization state and a second polarization state at the same time, and only the second polarization state is adjusted subsequently. The measurement light 2P of the second polarization state can be transmitted after entering the polarization beam splitter 310 , and then enters the quarter wave plate 320 . The measurement light 2P of the second polarization state can become a left-handed circularly polarized light 2L (at the viewing angle of the MEMS mirror module 400 ) after passing through the quarter wave plate 320 , and after being reflected by the MEMS mirror module 400 , the 1/4 wave plate 320 is incident again. When incident on the 1/4 wave plate 320, in terms of the observation angle of the 1/4 wave plate 320, it is the right-handed circularly polarized light 2R incident, and the emitted laser beam changes to the measurement of the first polarization state Light 2S. The polarization beam splitter 310 reflects the measurement light 2S of the first polarization state, and the measurement light subsequently passes through the beam splitting module 200 and can be reflected to the second path, and then enters the measurement device 600 .

此外，為了確保入射進極化分光器310的雷射光束為線性偏振光，如圖1的示例所示，於極化分光器310與分光模組200之間可進一步加入極化器330。該極化器330可以是具過濾性質的檢偏器或是可調整偏振方向的起偏器(例如1/2波板)。是以，該極化器330用於使通過之光線轉換為第一偏振態的光線。In addition, in order to ensure that the laser beam entering the polarization beam splitter 310 is linearly polarized light, as shown in the example of FIG. 1 , a polarizer 330 may be further added between the polarization beam splitter 310 and the beam splitting module 200 . The polarizer 330 can be an analyzer with filtering properties or a polarizer with adjustable polarization direction (eg, a 1/2 wave plate). Therefore, the polarizer 330 is used to convert the passing light into the light of the first polarization state.

接著請同時參照圖1及圖2，圖2為本發明一實施例之光控制模組內使用1/4波板的原理示意圖。如圖2所示，1/4波板320左邊的入射光線為線性偏振光，具有線性偏振方向322，該線性偏振方向322與1/4波板320之光軸321間的夾角為θ。當夾角θ為±45度時，自1/4波板320右邊出射的光線會形成圓形偏振光。當夾角θ非為0度或±45度時，自1/4波板320右邊出射的光線會形成橢圓偏振光。Next, please refer to FIG. 1 and FIG. 2 at the same time. FIG. 2 is a schematic diagram of the principle of using a quarter wave plate in a light control module according to an embodiment of the present invention. As shown in FIG. 2 , the incident light on the left side of the quarter wave plate 320 is linearly polarized light and has a linear polarization direction 322 . The angle between the linear polarization direction 322 and the optical axis 321 of the quarter wave plate 320 is θ. When the included angle θ is ±45 degrees, the light emitted from the right side of the 1/4 wave plate 320 will form circularly polarized light. When the included angle θ is not 0 degrees or ±45 degrees, the light emitted from the right side of the quarter wave plate 320 will form elliptically polarized light.

圖2示例者為夾角θ為45度，對於微機電反射鏡模組400來說，所觀察到的出射光線係為右旋的圓形偏振光。由於微機電反射鏡模組400係為反射鏡，故反射回1/4波板320的光線會恰好相反，亦即，右旋的圓形偏振光入射微機電反射鏡模組400後，反射出來的光線對於1/4波板320的觀察角度來說，變為左旋的圓形偏振光，進而藉由1/4波板320的特性讓左旋的圓形偏振光轉變回線性偏振光且偏振態亦被轉換(第一偏振態變為第二偏振態，或第二偏振態變為第一偏振態)。其中，在橢圓偏振光的狀態下亦同。In the example shown in FIG. 2 , the included angle θ is 45 degrees. For the MEMS mirror module 400 , the observed outgoing light is clockwise circularly polarized light. Since the MEMS mirror module 400 is a mirror, the light reflected back to the quarter wave plate 320 is just opposite, that is, the right-handed circularly polarized light enters the MEMS mirror module 400 and is reflected out For the viewing angle of the 1/4 wave plate 320 , the light becomes a left-handed circularly polarized light, and then the left-handed circularly polarized light is converted back to a linearly polarized light and the polarization state is changed by the characteristics of the 1/4 wave plate 320 is also converted (the first polarization state becomes the second polarization state, or the second polarization state becomes the first polarization state). However, the same applies to the state of elliptically polarized light.

是以，1/4波板320與極化分光器310的搭配，使用在微機電反射鏡模組400上，即可具有光線通過極化分光器310時不會被大幅衰減強度的優點(因偏振態的匹配)，且同時又可對微機電反射鏡模組400形成0度入射(因分光鏡的使用)，讓雷射共焦量測系統達到低失真且低光強損耗的目的。Therefore, the combination of the 1/4 wave plate 320 and the polarizing beam splitter 310 can be used on the MEMS mirror module 400 to have the advantage that the intensity of light will not be greatly attenuated when passing through the polarizing beam splitter 310 (due to polarization state matching), and at the same time, it can form a 0-degree incidence to the MEMS mirror module 400 (due to the use of a beam splitter), so that the laser confocal measurement system can achieve the purpose of low distortion and low light intensity loss.

本發明在上文中已以較佳實施例揭露，然熟習本項技術者應理解的是，該實施例僅用於描繪本發明，而不應解讀為限制本發明之範圍。應注意的是，舉凡與該實施例等效之變化與置換，均應設為涵蓋於本發明之範疇內。因此，本發明之保護範圍當以申請專利範圍所界定者為準。The present invention has been disclosed above with preferred embodiments, but those skilled in the art should understand that the embodiments are only used to describe the present invention, and should not be construed as limiting the scope of the present invention. It should be noted that all changes and substitutions equivalent to this embodiment should be considered to be included within the scope of the present invention. Therefore, the protection scope of the present invention should be defined by the scope of the patent application.

100:雷射光源裝置 110:雷射源 120:光纖 130:準直透鏡 200:分光模組 300:光控制模組 310:極化分光器 320:1/4波板 321:光軸 322:線性偏振方向 330:極化器 400:微機電反射鏡模組 500:聚焦模組 511:掃描透鏡 512:鏡筒透鏡 520:分光裝置 530:物鏡 600:量測裝置 610:聚焦透鏡 620:針孔裝置 630:光電倍增管 700:載台 1P:第二偏振態的雷射光束 1S:第一偏振態的雷射光束 1R:右旋的圓偏振光 1L:左旋的圓偏振光 2P:第二偏振態的量測光 2R:右旋的圓偏振光 2L:左旋的圓偏振光 2S:第一偏振態的量測光 θ:夾角 100: Laser light source device 110: Laser source 120: Fiber 130: collimating lens 200: Spectral module 300: Light control module 310: Polarization beam splitter 320:1/4 wave plate 321: Optical axis 322: Linear polarization direction 330: Polarizer 400: MEMS mirror module 500: Focus Module 511: Scanning Lens 512: Tube lens 520: Spectroscopic device 530: Objective lens 600: Measuring device 610: Focusing Lens 620: Pinhole Device 630: Photomultiplier tube 700: Stage 1P: Laser beam of second polarization state 1S: The laser beam of the first polarization state 1R: Right-handed circularly polarized light 1L: Left-handed circularly polarized light 2P: Measurement light of the second polarization state 2R: Right-handed circularly polarized light 2L: Left-handed circularly polarized light 2S: Measurement light of the first polarization state θ: included angle

[圖1]係為本發明一實施例之雷射共焦量測系統的示意圖。 [圖2]係為本發明一實施例之光控制模組內使用1/4波板的原理示意圖。 1 is a schematic diagram of a laser confocal measurement system according to an embodiment of the present invention. [FIG. 2] is a schematic diagram of the principle of using a quarter wave plate in a light control module according to an embodiment of the present invention.

100:雷射光源裝置 100: Laser light source device

110:雷射源 110: Laser source

120:光纖 120: Fiber

130:準直透鏡 130: collimating lens

200:分光模組 200: Spectral module

300:光控制模組 300: Light control module

310:極化分光器 310: Polarization beam splitter

320:1/4波板 320:1/4 wave plate

330:極化器 330: Polarizer

400:微機電反射鏡模組 400: MEMS mirror module

500:聚焦模組 500: Focus Module

511:掃描透鏡 511: Scanning Lens

512:鏡筒透鏡 512: Tube lens

520:分光裝置 520: Spectroscopic device

530:物鏡 530: Objective lens

600:量測裝置 600: Measuring device

610:聚焦透鏡 610: Focusing Lens

620:針孔裝置 620: Pinhole Device

630:光電倍增管 630: Photomultiplier tube

700:載台 700: Stage

1P:第二偏振態的雷射光束 1P: Laser beam of second polarization state

1S:第一偏振態的雷射光束 1S: The laser beam of the first polarization state

1R:右旋的圓偏振光 1R: Right-handed circularly polarized light

1L:左旋的圓偏振光 1L: Left-handed circularly polarized light

2P:第二偏振態的量測光 2P: Measurement light of the second polarization state

2R:右旋的圓偏振光 2R: Right-handed circularly polarized light

2L:左旋的圓偏振光 2L: Left-handed circularly polarized light

2S:第一偏振態的量測光 2S: Measurement light of the first polarization state

Claims

一種雷射共焦量測系統的光控制模組，係用於在一微機電反射鏡模組的進/出光路徑上進行控制，並用於接收第一偏振態的雷射光束，以及用於接收來自待測物且為第二偏振態的量測光以提供至該微機電反射鏡模組，其特徵在於：該光控制模組係用以使出射且射向該微機電反射鏡模組的該雷射光束係為圓形偏振光或橢圓偏振光，該光控制模組並用以使反射自該微機電反射鏡模組的該雷射光束轉換為線性偏振光，該第一偏振態係正交於該第二偏振態。A light control module of a laser confocal measurement system is used for controlling the incoming/outgoing light path of a micro-electromechanical mirror module, for receiving a laser beam of a first polarization state, and for receiving The measurement light from the object to be tested and in the second polarization state is provided to the MEMS mirror module, wherein the light control module is used to make the light emitted and directed towards the MEMS mirror module The laser beam is circularly polarized light or elliptically polarized light, the light control module is used to convert the laser beam reflected from the MEMS mirror module into linearly polarized light, and the first polarization state is positive in the second polarization state.

如請求項1所述之光控制模組，其中該光控制模組包含：一極化分光器，反射該第一偏振態的入射光，以及透射該第二偏振態的入射光；及一1/4波板，配置於該極化分光器與該微機電反射鏡模組之間，其中，自該極化分光器出射且遠離該微機電反射鏡模組的該雷射光束係為該第二偏振態，自該極化分光器出射且遠離該微機電反射鏡模組的該量測光係為該第一偏振態。 The light control module according to claim 1, wherein the light control module comprises: a polarization beam splitter that reflects incident light of the first polarization state and transmits incident light of the second polarization state; and A 1/4 wave plate, disposed between the polarization beam splitter and the MEMS mirror module, Wherein, the laser beam emitted from the polarization beam splitter and away from the MEMS mirror module is in the second polarization state, and the amount of the laser beam emitted from the polarization beam splitter and away from the MEMS mirror module The photometric system is the first polarization state.

如請求項2所述之光控制模組，其中更包含一極化器，配置於該極化分光器接收該第一偏振態之該雷射光束的這一側，該極化器係使通過之光線轉換為該第一偏振態的光線。The light control module according to claim 2, further comprising a polarizer disposed on the side of the polarization beam splitter that receives the laser beam of the first polarization state, the polarizer makes the laser beam of the first polarization state pass through The light is converted into light of the first polarization state.

如請求項1所述之光控制模組，其中該第一偏振態為S偏振，該第二偏振態為P偏振。The light control module of claim 1, wherein the first polarization state is S polarization, and the second polarization state is P polarization.

如請求項2至4中任一項所述之光控制模組，其中自該極化分光器出射且射向該微機電反射鏡模組之該雷射光束的線偏振方向係與該1/4波板之光軸間具有±45度的夾角。The light control module according to any one of claims 2 to 4, wherein the linear polarization direction of the laser beam emitted from the polarization beam splitter and directed to the MEMS mirror module is the same as the 1/ The optical axes of the 4-wave plates have an included angle of ±45 degrees.

一種雷射共焦量測系統，用於在第一光路徑上將雷射光束提供至待測物，並接收來自該待測物的量測光以使該量測光被導引至量測裝置，該雷射共焦量測系統包含：一分光模組，配置為透射該雷射光束，以及反射該量測光至第二路徑，使該量測光入射至該量測裝置；一微機電反射鏡模組；一聚焦模組，配置為透射作為掃描光束的該雷射光束，以及透射來自該待測物的該量測光；及一光控制模組，配置為調整來自該分光模組的該雷射光束以入射至該微機電反射鏡模組，及接收來自該微機電反射鏡模組所反射的該雷射光束以入射至該聚焦模組，該光控制模組係使出射且射向該微機電反射鏡模組的該雷射光束係為圓形偏振光或橢圓偏振光，以及使反射自該微機電反射鏡模組的該雷射光束轉換為線性偏振光，以及使出射且遠離該微機電反射鏡模組的該量測光係為第一偏振態的線性偏振光，以及使出射且遠離該微機電反射鏡模組的該雷射光束係為第二偏振態的線性偏振光，該第一偏振態係正交於該第二偏振態。 A laser confocal measurement system for providing a laser beam to an object to be measured on a first optical path, and receiving measurement light from the object to be measured so that the measurement light is guided to a measurement device, the laser confocal measurement system includes: a beam splitting module configured to transmit the laser beam and reflect the measurement light to the second path, so that the measurement light is incident on the measurement device; a MEMS mirror module; a focusing module configured to transmit the laser beam as a scanning beam and transmit the measurement light from the object to be measured; and a light control module configured to adjust the laser beam from the beam splitting module to be incident on the MEMS mirror module, and receive the laser beam reflected from the MEMS mirror module to be incident on the MEMS mirror module The focusing module and the light control module make the laser beam emitted from the MEMS mirror module be circularly polarized light or elliptically polarized light, and make the laser beam reflected from the MEMS mirror module The laser beam is converted into linearly polarized light, and the measuring light that exits and is far away from the MEMS mirror module is linearly polarized light of the first polarization state, and the exiting and away from the MEMS mirror module is linearly polarized light. The laser beams of the group are linearly polarized light of a second polarization state, and the first polarization state is orthogonal to the second polarization state.

如請求項6所述之雷射共焦量測系統，其中該光控制模組包含：一極化分光器，接收來自該分光模組的該雷射光束，該極化分光器用於反射該第一偏振態的入射光，以及透射該第二偏振態的入射光；及一1/4波板，配置於該極化分光器與該微機電反射鏡模組之間。 The laser confocal measurement system according to claim 6, wherein the light control module comprises: a polarization beam splitter for receiving the laser beam from the beam splitting module, the polarization beam splitter is used for reflecting the incident light of the first polarization state and transmitting the incident light of the second polarization state; and A 1/4 wave plate is arranged between the polarization beam splitter and the MEMS mirror module.

如請求項7所述之雷射共焦量測系統，其中更包含一極化器，配置於該極化分光器與該分光模組之間，該極化器係使通過之光線轉換為該第一偏振態的光線。The laser confocal measurement system according to claim 7, further comprising a polarizer disposed between the polarization beam splitter and the beam splitting module, the polarizer converts the passing light into the beam splitter light of the first polarization state.

如請求項8所述之雷射共焦量測系統，其中該極化器係為一檢偏器或一起偏器。The laser confocal measurement system according to claim 8, wherein the polarizer is an analyzer or a polarizer.

如請求項7至9中任一項所述之雷射共焦量測系統，其中自該極化分光器出射且射向該微機電反射鏡模組之該雷射光束的線偏振方向係與該1/4波板之光軸間具有±45度的夾角。The laser confocal measurement system according to any one of claims 7 to 9, wherein the linear polarization direction of the laser beam emitted from the polarization beam splitter and directed to the MEMS mirror module is the same as The optical axes of the 1/4 wave plate have an included angle of ±45 degrees.