Abstract:
An absolute distance measuring method using an optical frequency generator and a measuring system thereof are provided to measure the length precisely by measuring the absolute distance. An optical frequency generating module(100) includes an external cavity laser diode(101), a femtosecond laser(102), a polarization beam splitter(103), a polarizer(104), an optical filter(105), and avalanche photo diode(106), and a phase locked loop(107). The external cavity laser diode generates the laser of the short wavelength and the variable range of the wavelength is 765 to 781 nm. The femtosecond laser generates the laser pulse with a multi wavelength. The polarization beam splitter transmits or reflects the laser of the multi wavelength and the short wavelength according to the polarization direction.
Abstract:
A white-light scanning interferometer for large-sized three-dimensional profile measurement using macro lenses and a method for measuring a three-dimensional profile are provided to change the most suitable visual region for the size of an object to be measured by using the zoom function of a macro lens. A light source(100) radiates white light. A light splitter(110) divides the white light into measuring light and reference light in order to irradiate the white light on a measuring surface and a reference surface. A macro lens(140) receives an interference pattern by using the reference light reflected from the measuring surface and the reference surface. An image acquisition unit(150) acquires the received interference pattern of the macro lens. The shape of the measuring surface is measured by using the interference pattern of the image acquisition unit.
Abstract:
본 발명은 유리기판의 돌출 결함 형상 측정장치 및 방법에 관한 것으로서, 평행광을 유리기판(1)에 투사시키는 평행광생성수단(110)과, 유리기판(1)에 반사되는 광을 제 1 및 제 2 광으로 분할하는 광분할기(120)와, 제 1 광을 기준광으로 생성시키는 기준광생성수단(130)과, 제 2 광을 측정광으로서 기준광에 대한 광경로차를 조절하는 측정광조절수단(140)과, 유리기판(1)과 동일한 재질 및 두께로 형성됨과 아울러 기준광 또는 측정광의 경로상에 설치되어 이들의 경로를 보상하는 리타더(150)와, 기준광과 측정광을 동일 경로로 출사하는 편광분할기(160)와, 편광분할기(160)로부터 출사되는 기준광과 측정광의 위상을 공간적으로 천이시켜서 복수개의 간섭신호를 출사하는 공간위상천이수단(180)과, 공간위상천이수단(180)에 의해 천이된 복수개의 간섭신호를 동시에 획득하는 광검출기(190)를 포함한다. 따라서, 본 발명은 유리기판과 동일한 재질 및 두께를 가진 리타더를 사용하여 기준광이나 측정광을 유리기판의 상면 또는 하면에서 반사되는 광들중 용이하게 선택할 수 있도록 함으로써 유리기판상에서 3차원 돌출 결함의 위치 구분이 가능하며, 유리기판의 돌출 결함의 3차원 이미지는 물론 유리기판에서 돌출 결함을 발생시키는 결함의 2차원 이미지를 획득함으로써 결함의 원인 및 종류 등에 대한 분석이 가능하도록 하는 효과를 가지고 있다.
Abstract:
본 발명은 진동에 둔감한 간섭계에 관한 것으로, 측정물체의 진동이 기준파면과 측정파면에 공통적으로 존재함으로써 움직이는 물체의 형상을 안정적으로 측정할 수 있으며, 기준면으로 인해 생성되는 오차를 없애기 위해 단일모드 광섬유에서 조사되는 구면파를 직접 기준파면으로 사용함으로써 시스템 오차를 최소화 할 수 있다. 따라서, 본 발명의 장치는 정밀한 측정을 위한 공간위상천이 장치가 구비되며, 실시간으로 측정대상 물체의 임의 형상을 측정할 수 있다. 간섭계, 광섬유, 공간위상천이,
Abstract:
In the method and a device for detecting the phase of a moving object using a heterodyne interferometer, a heterogeneous mode helium-neon laser is used as a direct light source to increase a measuring speed, a measuring resolution, and minimize the loss of the light source. Signals, which have only a frequency difference between reference signals or measured signals and arbitrary signals, are extracted from signals which are obtained by multiplying the arbitrary frequency signals by the reference or measured signals. After frequencies of the reference and measured signals are converted, a phase difference of the extracted signals and displacement of the moving object is measured. The system includes a laser light source, an optical interferometer, a frequency converter, and a phase measurer. The light source uses output light, emitted from the laser generator, which is stabilized in frequency, and has two frequencies which are at right angles to each other and linearly polarized.
Abstract:
PURPOSE: A three-dimensional shape measuring unit using multi-channel phase-shifting Moire technique is provided to simultaneously gather plural Moire fringes and to obtain all measurement information about a predetermined surface of a three-dimensional shape by employing a hologram as a beam splitter. CONSTITUTION: A three-dimensional shape measuring unit using multi-channel phase-shifting Moire technique includes a projection system, an imaging system, a Moire fringe obtaining part, and a central processing part. The projection system projects lattice patterns on an object. The imaging system is formed such that the lattice pattern is image-formed on the basis of a reference lattice. The Moire fringe obtaining part obtains Moire fringes derived from interference of changed lattice patterns and the reference lattice patter.
Abstract:
PURPOSE: A Fizeau interferometer using an oblique section fiber light source is provided to improve the reliability of measuring results by removing beam splitting elements from a measuring wavefront. CONSTITUTION: A Fizeau interferometer includes a single mode fiber(12), a laser generator(11) for outputting beams to the single mode fiber, a collimator for converting the light of the laser generator to the parallel light, a reference plate(17) for transmitting and reflecting the parallel light to a target(18) in order to generate a reference wavefront, and a CCD camera(14) for detecting an interference fringe of the reference wavefront. The Fizeau interferometer further includes an oblique section fiber light source which is coupled to the single mode fiber. A beam split coating layer is formed on an oblique section of the oblique section fiber light source.