1、研磨加工基本知识讲义一、 镜片加工流程及基本知识1、 镜片加工流程:切削 研削 研磨 洗净2、 切削的基本知识:切削:国内叫“粗磨” ,国外叫 NCG,为英文“球面创成”之缩写。切削目的:去除材料硝材表面层,深度为 0.50.6mm.。由于硝材压型时精度不高,不加大加工余量就不能达到镜片所需尺寸(包括曲率、肉厚等) 。3、 研削的基本知识:研削(也称精磨或砂挂) ,是镜片研磨前的极为重要的工序,研削加工的主要目的为: 加工出研磨工序所需要的表面精细度。研削分为两道工序:A、第一道工序称 S1,用 1200#1500#的钻石粒。B、第二道工序称 S2,用 1500#2000#的树指进行加工。 加
2、工出研磨工序所需要的球面精度。 满足镜片中心肉厚要求,在规定的尺寸公差之内。 研削品质的好坏对研磨后镜片的品质影响极大。如研磨不良伤痕() 、砂目() 、肉厚、面不等不良均与研削有直接关系,研削品质的好坏决定研磨品质的优劣。二、 研磨加工基本知识:硝材在经过切削及研削,其基本尺寸及表面光洁度已经形成,但仍不能满足客 户 光 学 上 的要 求 , 必 须 进 行 研 磨 工 序 , 研 磨 是 获 得 光 学 表 面 的 最 主 要 的 工 序 :1、 研磨加工的目的: 去除精度的破坏层,达到规定的外观限度要求。 精修面形,达到图面规置之不理的曲率半径 R 值,满足面本数 NR 要求及光圈局部允
3、差(亚斯)的要求。2、 研磨的机理: 机械研削理论。 化学学说。 表面流动理论。3、 光圈的识别与度量(我们通常说的面即光圈) 什么是光圈?被检查镜片表面面形与标准曲率半径的原器面形有偏差时,它们之间含形成对称的契形空气间隙,从而形成等厚干涉条纹,有日光照射下可见到彩色光环(此时空气隙,呈环形对称) ,这种彩色的光环称为光圈,我们通常观察光圈数(即面本数)以红色光带为准。这 是 因 为 红 色 光 带 较 宽 ( 波 长 范 围 为0.62um0.78um) , 看 起 来 清 晰 明 亮 。 面本数的识别与度量有原器检查镜片时,如果二者是边缘接触(中间有空气层) ,从正方稍加压力 P,干涉条
4、纹从外向中心部移动即向内缩,称为低光圈或负光圈(图 A) ,如果二者是从中间开始接触(边缘有空气隙) ,从正上方稍加压力 P,干涉条纹从中心向边缘移动(或向外扩散)称为高光圈或正光圈(图 B) 此时判定其面本数是以红色光带为标准,垂直观察有几个圆环带即面本数为几本,如图 A 为 NR=-3 本,如图 B 为 NR=+3 本。 亚斯的识别与度量目前公司将面精度的中高、中低、垂边、分散或边等统称为亚斯,亚斯一定要满足作业标准的要求,超过标准含影响镜头的解像,所以亚斯是一个非常重要的指标, P P图 A 图 B光带向内缩光带向外扩红色光带And grinding Basic knowledge ha
5、ndouts Lens processing processes and basic knowledge1, lens processing process:Wash cutting grinding grinding 2, the cutting of the basics:Cutting: Domestic called “coarse“, abroad called the NCG, English spherical Creation “abbreviation.Cutting Objective: To remove the material the surface of the g
6、lass material layer and a depth of 0.5 to 0.6mm.Due to the type of glass material pressure accuracy is not high, do not increase the allowance can not be required to reach the lens size (including curvature, flesh, etc.).3, the grinding of the basics:Grinding (also known as grinding or sand hanging)
7、 is an extremely important step in front of the lens grinding Grinding main purpose: machined surface fineness of the grinding step.Grinding is divided into two processes:A first process known as S1, 1200 # to 1500 # diamond particles.B, the second process known as S2, 1500 # # 2000 resin processing
8、. processing spherical precision polishing step.(3) to meet the center of the lens flesh requirements within the specified dimensional tolerances.(4) grinding quality is good or bad quality of the lens grinding a great impact.Such as grinding bad scars (Cash), graining (su), flesh, ranging from bad
9、to have a direct relationship with the grinding surface, the pros and cons of grinding quality determines the quality of the grinding quality.Grinding Basics:Nitrate material in its basic dimensions and surface finish has been formed after cutting and grinding, but it still can not meet the requirem
10、ents of the customer optical polishing step must be carried out, is the most important step to obtain the optical surface polishing:1, the purpose of grinding:(1) removal of the accuracy of the destruction layer, to achieve the required appearance limit requirements. the fine shave shaped to drawing
11、 requirements ignore the radius of curvature R, meet the requirements of the surface number NR requirements and aperture local tolerance (Elias).2, the grinding mechanism: mechanical RESEARCH cut theory.(2) chemical theory.(3) surface flow theory.3, identification and measurement of the aperture (we
12、 usually say that the surface of the iris) What is Aperture?Check the surface shape of the lens surface with the standard radius of curvature of the original surface shape deviation between them containing a symmetrical wedge-shaped air gap is formed, thereby forming fringes of equal thickness, the
13、color can be seen under the sunlight halo (air gap annular symmetry), this halo of color called the iris aperture surface (the number), we usually observe the red band of light.This is because the red wide band of light (wavelength range 0.62um 0.78um), looks clear and bright. face identification an
14、d measurement of the number ofOriginal check lenses, if both the edge of the contact (the air layer in the middle), a little from the affirmative pressure P, interference fringes i.e. inwardly retracted portion moving from the center outward, as low the aperture or negative aperture (A) , if both ar
15、e from the middle into contact with the air gap (edge), a little from the top of the positive pressure P, the interference fringes move from the center to the edge (or outward diffusion) called high aperture or positive aperture (Figure B)Determine the number of its surface is the red band of light
16、as a standard vertical observation of several rings with that surface of the number of the Figure A Figure B is NR = -3, for NR = +3 this.(3) Elias identification and measurementSurface accuracy high, low, slouch, dispersed or side collectively referred to as Aspen, Aspen must meet the standard requirements of the job, more than the standard containing the impact of the resolution of the lens, so Aspen is a very important indicators