阅读说明：本技术 一种光学元件亚表面缺陷深度信息的检测装置及检测方法 (Detection device and detection method for depth information of subsurface defect of optical element ) 是由 田爱玲 邱啸天 张英鸽 王红军 王春阳 刘雪莲 刘丙才 朱学亮 于 2019-10-11 设计创作，主要内容包括：本发明涉及一种光学元件亚表面缺陷深度信息的检测装置及检测方法,由光源调制组件、缺陷深度检测组件、二维移动平台以及计算机控制平台组成,所述光源调制组件的光路垂直于二维移动平台布置,从上至下依次包括紫外激光器、窄带滤光片,光束整形组件；缺陷检测组件的光路与光源调制组件的光路成夹角布置,依次包括窄带滤光片,显微镜头和CCD探测器；计算机控制平台分别与CCD探测器和二维移动平台相连。本发明的装置和方法克服了现有技术存在的检测效率极低、存在严重效益低、二次损伤和定位困难的缺点。(The invention relates to a detection device and a detection method for subsurface defect depth information of an optical element, which consists of a light source modulation component, a defect depth detection component, a two-dimensional moving platform and a computer control platform, wherein the light path of the light source modulation component is arranged perpendicular to the two-dimensional moving platform and sequentially comprises an ultraviolet laser, a narrow-band filter and a light beam shaping component from top to bottom; the optical path of the defect detection component and the optical path of the light source modulation component are arranged at an included angle and sequentially comprise a narrow-band filter, a microscope lens and a CCD detector; the computer control platform is respectively connected with the CCD detector and the two-dimensional moving platform. The device and the method overcome the defects of extremely low detection efficiency, low serious benefit, secondary damage and difficult positioning in the prior art.)

1. An optical element subsurface defect depth information detection device is characterized in that: the device comprises a light source modulation component, a defect depth detection component, a two-dimensional moving platform (5) and a computer control platform, wherein the light path of the light source modulation component is arranged perpendicular to the two-dimensional moving platform (5), and sequentially comprises an ultraviolet laser (1), a narrow-band filter (2) and a light beam shaping component (3) from top to bottom; the optical path of the defect detection component and the optical path of the light source modulation component are arranged at an included angle and sequentially comprise a narrow-band filter (6), a microscope lens (7) and a CCD detector (8); the computer control platform (9) is respectively connected with the CCD detector (8) and the two-dimensional moving platform (5).

2. The method of claim 1 for performing a method of non-destructive inspection of subsurface defects in an optical component, comprising: firstly, a measured piece (4) with quantum dots permeated in subsurface defects is placed on a two-dimensional translation table (5), an ultraviolet laser (1) emits ultraviolet laser, the ultraviolet laser firstly screens required wavelengths through a narrow-band optical filter (2), then the laser is shaped into thin beams through a beam shaping assembly, and the thin beams penetrate through the surface of the measured piece (4) to excite the quantum dots permeated in the subsurface of the sample piece; quantum dots inside the tested piece (4) are excited to generate scattered fluorescence information, and the scattered fluorescence information is imaged on a CCD detector (8) through a microscope lens (7) after being subjected to wavelength screening by a narrow-band filter (6); the computer control platform (9) obtains depth information of the sub-surface defects of the measured sample by combining with a CCD camera calibration result according to CCD imaging information, and meanwhile, the computer control platform (9) can control the two-dimensional displacement platform (5) to move in real time to obtain real-time light field distribution of the sub-surface defects at different positions of the measured sample (8).

Technical Field

The invention relates to the technical field of precision optical detection, in particular to a detection device and a detection method for subsurface defect depth information of an optical element.

Background

In the process of precision optical elements, such as grinding, polishing and the like, defects such as cracks, pits and the like are easily formed on the surface and the subsurface of the optical element, generally, for the precision optical elements, the horizontal size of the surface defect is in the submicron and nanometer level, and the longitudinal depth size is from several micrometers to hundreds of micrometers. When incident light irradiates on the surface defect of the optical element, strong diffraction and scattering effects are generated, and the quality of light beam transmission energy in an optical system is greatly reduced. Therefore, the detection device and detection technology for the surface and subsurface defects of the optical element are the focus of attention in the industry.

At present, the detection of defects mainly takes detection devices such as total internal reflection intensity analysis, laser confocal microscopy, optical microscopy and the like as main devices, and generally comprises a laser source emitting assembly, a light beam shaping assembly, a prism for adjusting direction and an image receiving device.

Disclosure of Invention

The invention provides a nondestructive detection device and a detection method for the subsurface defect depth of an optical element, which aim to overcome the defects of extremely low detection efficiency, low serious benefit, secondary damage and difficult positioning in the prior art.

In order to achieve the purpose of the invention, the technical scheme provided by the invention is as follows:

a detection device for sub-surface defect depth information of an optical element comprises a light source modulation component, a defect depth detection component, a two-dimensional moving platform and a computer control platform, wherein the light path of the light source modulation component is arranged perpendicular to the two-dimensional moving platform and sequentially comprises an ultraviolet laser, a narrow-band filter and a light beam shaping component from top to bottom; the optical path of the defect detection component and the optical path of the light source modulation component are arranged at an included angle and sequentially comprise a narrow-band filter, a microscope lens and a CCD detector; the computer control platform is respectively connected with the CCD detector and the two-dimensional moving platform.

According to the device, a detected piece with quantum dots permeated in the subsurface defect is placed on a two-dimensional translation table, an ultraviolet laser emits ultraviolet laser, the ultraviolet laser firstly screens required wavelength through a narrow-band filter, then the laser is shaped into a thin beam through a beam shaping assembly, and the thin beam penetrates through the surface of the detected piece to excite the quantum dots permeated into the subsurface of a sample piece; quantum dots in the tested piece are excited to generate scattered fluorescence information, and the scattered fluorescence information is imaged on a CCD detector through a microscope lens after the wavelength is screened by a narrow-band filter; and the computer control platform can control the two-dimensional displacement platform to move in real time to obtain the real-time light field distribution of the subsurface defects at different positions of the measured sample.

Compared with the prior art, the invention has the advantages that:

1. the quantum dot marked optical element surface defects are extended to marked optical element subsurface defects.

2. The position of the marked quantum dot is detected by utilizing the wavelength difference between the excitation wavelength and the emission wavelength of the quantum dot in a non-contact optical detection mode, so that the non-destructive detection is realized.

3. The depth detection of the subsurface defect is converted into the depth detection of the quantum dots by utilizing the characteristic of real-time excitation of the quantum dots, so that the detection difficulty is greatly reduced, and the detection speed is improved.

4. The machine vision imaging identification technology can replace the interference of human eye subjective factors, thereby not only reducing the artificial burden, but also improving the detection speed and the accuracy and consistency of the detection result, and simultaneously realizing real-time online scanning measurement.

Drawings

FIG. 1 is a schematic structural diagram of an optical element defect detecting apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the optical path principle for detecting the depth of subsurface defects used in the present invention;

FIG. 3 is a schematic diagram of a subsurface defect of an optical element according to an embodiment of the present invention.

In the figure, 1-an ultraviolet laser, 2-a narrow-band optical filter, 3-a beam shaping assembly, 4-a measured piece, 5-a two-dimensional moving platform, 6-a narrow-band optical filter, 7-a microscope lens, 8-a CCD detector and 9-a computer control platform.

The specific implementation mode is as follows:

the present invention will be described in detail below with reference to the drawings and examples.

Referring to fig. 1, the detection apparatus for detecting the depth of a subsurface defect of a nondestructive optical element provided by the invention mainly comprises a light source modulation component, a defect depth detection component, a two-dimensional moving platform and a computer control platform, wherein a light path of the light source modulation component is arranged perpendicular to the two-dimensional moving platform 5 and sequentially comprises an ultraviolet laser 1, a narrow-band filter 2 and a light beam shaping component 3 from top to bottom; the optical path of the defect detection component and the optical path of the light source modulation component form an included angle, and the optical path of the defect detection component and the optical path of the light source modulation component sequentially comprise a narrow-band filter 6, a microscope lens 7 and a CCD detector 8; the computer control platform 9 is respectively connected with the CCD detector 8 and the two-dimensional moving platform 5.

The invention provides a method for detecting the depth of a subsurface defect of an optical element, which comprises the following steps: firstly, a measured piece 4 with quantum dots permeated in subsurface defects is placed on a two-dimensional translation table 5, an ultraviolet laser 1 emits ultraviolet laser, the ultraviolet laser firstly passes through a narrow-band filter 2 to screen required wavelengths, then a beam shaping assembly shapes the laser into thin beams, and the thin beams penetrate through the surface of the measured piece 4 to excite the quantum dots permeated into the subsurface of a sample piece; quantum dots in the tested piece 4 are excited to generate scattered fluorescence information, and the scattered fluorescence information is imaged on a CCD detector 8 through a microscope lens 7 after the wavelength is screened by a narrow-band filter 6; the computer control platform 9 obtains depth information of the sub-surface defects of the measured sample according to the CCD imaging information and by combining with the CCD camera calibration result, and meanwhile, the computer control platform 9 can control the two-dimensional displacement platform 5 to move in real time to obtain real-time light field distribution of the sub-surface defects at different positions of the measured sample 8.

Referring to fig. 2, the stimulated scattering fluorescence information of the quantum dots permeating into the subsurface defect of the measured piece 4 is imaged on the CCD surface, and the end coordinates of the detection surface are a 'and B', and the positional relationship between the depth of the subsurface defect and the photosensitive surface of the detector can be obtained as follows:

in the formula, the first and second sets of data are represented,

indicating the depth of the subsurface defect to be determined, L₁Is the distance L from the intersection point A of the light and the sample surface to the microscopic imaging lens 7₂Showing the distance of the microlens 7 from the photosensitive surface of the CCD detector 8,

the receiving surface of the CCD detector 8 is shown, alpha represents the included angle between the incident light beam and the surface scattered light of the measured piece, and beta represents the included angle between the CCD detector 8 and the surface scattered light of the sample.

Calibrating the CCD camera after debugging all light paths, and shooting by using the calibrated CCD detector

The calibration result is combined to obtain the measured value in real time

The value is obtained.

Referring to fig. 3, a schematic diagram of an optical element subsurface defect. The quantum dots can be deep into a 100-micron deep subsurface crack layer for marking according to size advantages, and further the depth detection of subsurface defects can be realized by detecting the positions of the quantum dots.

It will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.