Research Of Zoom Structured Light Depth Imaging Optical System Based On Liquid Lens

In recent years,depth contour imaging technology has been widely used in clinical medicine,cultural relics protection,industrial production and so on.With the rapid development of computer technology,the speed of non-contact depth profile measurement became faster and faster,and the accuracy are higher.The work of this subject is to research the principle of liquid lens zoom,optical design and stray light of depth imaging system based on structured light.It has important practical significance in the process of social production,the main research contents include the following aspects:1.Introduced and classifies the depth imaging technology as a whole,and the application fields of depth imaging technology are briefly introduced.Combined with the related depth imaging products,the research status and progress of depth imaging technology at home and abroad are analyzed and summarized.Finally,the research contents and significance of this subject are summarized.2.Research on zoom principle of optical system based on liquid lens zoom: The zoom principle and related parameters of liquid lens of Optotune company are researched,the driving modes are explained and analyzed,The relation curve between the driving current of liquid lens and the focal length of lens is plotted.Then the Gauss formula is used to analyze and proof that when there is only one zoom lens,the optical system image surface will move back and forth,to achieve zoom optical system.The main surface of the optical system after adding protective glass is calculated.Finally,the internal refractive index of liquid lens is modeled to prepare for the follow-up of the optical design and simulation.3.Optical design of zoom structured light optical imaging system: Design of zoom structure of optical imaging system,the system in a small field of view,small-bore,high resolution optical system,the system uses 7 pieces spherical glass lens and 1 liquid lens structure.At 40lp/mm,the full field MTF system is better than 0.2,the system field curvature is less than 0.2,the distortion is less than 0.2%.The mechanical structure of the optical system is designed,the function of each structure is explained in detail.The structure of cylindrical micro-lens array is designed,the material is fused silica,the overall size of 10mm*10mm thickness of 1mm,width of the cycle is 1mm.4.Stray light study of liquid lens zoom structure optical imaging system: When the optical system has been processed,the experiment is carried out that there is obvious stray light in the optical system,the stray light need be researched and eliminated.Contrast analysis and experimental verification of coherent and incoherent imaging effects in Zemax non-sequential modes,the collimated LED light source is selected as the light source of the optical system.CODE V was used to qualitatively analyze ghost images and find out the possible ghost images,then,the qualitative analysis of the most likely surface is carried out by TracePro.The path through the ray tracing software of stray light,Stray light was eliminated by using a aperture.The stray light and extinction aperture of the stray light are quantitatively analyzed by TracePro.When the aperture is 3mm,the stray light can be effectively suppressed to ensure the high contrast of the image.5.Experiments on the system: The system can realize the projection distance of 227mm-256 mm regulation,during the focusing process,the image plane is always clear,the details of the image with high resolution,zoom system in the whole area,with the increase of projection distance,the imaging quality of optical system first increases and then decreases,the magnification of optical system increases,and the relative illuminance non-uniformity of optical system is less than 0.2.Through the depth reconstruction of the captured image,the depth information of the object is obtained,and the error is 0.37 mm.For the depth measurement of the image,the error is 0.34 mm and 0.37 mm,the depth measurement in the whole field of view,the minimum error of the central field of view is 0.1mm,and the measurement error is less than 0.6mm in the full field of view.