1、鏡頭光學規格的介紹鏡頭光學規格的介紹Curtis主題主題1Curtis內容大綱內容大綱1Pixel Size2Image Size3Image Circle 4Lens Composition5Field Of View(FOV)6F Number7Relative illumination(RI)8Chief Ray Angle(CRA)9Distortion10MTF11EFL12Back Focus Length(BFL)13Optical Total Length2LCM-*2Mega(Design)ItemLCM-*Sensor MI-XXXX,OV-XXXXPixel Size3.
2、2 x 3.2mImage Size D:5.6 mm (H:4.48 V:3.36)Image Circle 5.9mmLens Composition1G3PField Of View59.5(at SENSOR Diagonal)F NumberF/2.8Relative illumination at 100%of Image Height55%(at SENSOR Diagonal)Chief Ray AngleD:19.7 H:20.6 V:20.5TV Distortion1%MTF CenterCenter 54%180 LP/mm 50%200 LP/mm at 70%of
3、Image Heighth=70%T61%/S74%90LP/mm at 80%of Image Heighth=80%T59%/S69%90LP/mm at 90%of Image Heighth=90%T58%/S63%90LP/mm at 100%of Image Heighth=100%T59%/S72%90LP/mmFocus Lengthf=4.87mmBack Focus Length1.494mm Optical Total Length sensor size(D)。2、D+0.4mm(Package 公差)。MEMO:光學設計的考量,要從了解SENSOR開始。光學設計需與S
4、ENSOR達到最佳配合。PLWDP=Pixel sizesensor1Curtis5RatioType NameAspect Ratio(W:H)Diameter(mm)Width(mm)Height(mm)Diagonal(mm)Diameter/Diagonal1/3.64:37.067.064.003.005.001.411/3.24:37.947.944.543.425.681.401/34:38.478.474.803.606.001.411/2.74:39.419.415.374.046.721.401./2.54:310.1610.165.764.297.181.411/24:3
5、12.706.404.808.001.591/1.84:314.1114.117.205.359.001.572/34:316.9316.938.806.6011.001.5414:325.425.412.809.6016.001.594/34:333.8733.8717.4013.1021.781.561.83:245.7245.7223.7015.7028.401.6135mm film3:2n/a36.0024.0043.27n/aTypeSensorsensor2Curtis尺寸表6=79.Field Of ViewI0Image Intensity 流明I0Image Intensi
6、ty 流明光學設計需與SENSOR達到最佳配合。A、RI=50 at 30()MEMO:CCD所使用的F/#值較大(即光圈較小)。=2 tan-1 D/2f F/#:決定光通量、影像的亮度。如果使用過大的光圈,則會落於飽和區h=70%T61%/S74%90LP/mm因材料、加工、組立所產生的缺陷。1、反射式(Reflection type):干涉鍍膜。無Angle shift 問題false colorsFOV:Field Of ViewDfFOV=2 =2 tan-1 D/2f FOVsensor例:SENSOR對角線D=5mm,焦點距離f=3mm,則FOV為:FOV=2 =2 tan-1
7、5/2*3 =79.6(度)Curtis7F/#_1DfsensorF/#:決定光通量、影像的亮度。F/#=f/DI0 1/(F/#)2(進光量與進光量與F/#平方成反比平方成反比)。I0Image Intensity 流明流明 照度照度MEMO:F/#數值愈小 設計上困難度愈高。FOV愈大 設計上困難度愈高。Curtis8F/#_2比亮度亮兩倍。比亮度亮兩倍。例:F/#=2.8&4,焦點距離f=50mm,則入光大小為:F/#=f/D;D=f/F/#1、D(F/2.8)2、D(F/4.0)1、D(F/2.8)2、D(F/4.0)以圓面積計算公式計算如下:(R2)1、2 10022、2 491(
8、面積F/2.8)2*(面積F/4.0)Curtis9F/#_3CCD靈敏度較靈敏度較CMOS為高。為高。不致能區不致能區線性區線性區飽和區飽和區exposureresponseMEMO:CCD所使用的F/#值較大(即光圈較小)。如果使用過大的光圈,則會落於飽和區 使得成像品質不好。Curtis10050100MTF(lp/mm)MTF2截止頻率MTF Ci/CoCo:物:物Ci:像:像Optical systemNon-perfect lens因材料、加工、組立所產生的缺陷。100%70%Curtis12MTF3S:Sagittal,弧矢面,放射狀。T:Tangential,子午面,同心圓狀。
9、Curtis13OLPF2false colorsCurtis16IR_CUT Filter_114:33:24 IR_CUT FilterIR_CUT Filter1、反射式(Reflection type):干涉鍍膜。2、吸收式(Absorption type):藍玻璃。Curtis17IR_CUT Filter_2規格標示例:650nm 15nm T=50Curtis18IR_CUT Filter_3反射式反射式IR_CUT Filter的的Angle shift 問題問題入射角度增加,截止波長往短波長偏移。入射角度增加,截止波長往短波長偏移。吸收式吸收式_(藍玻璃、綠玻璃藍玻璃、綠玻璃
10、)無無Angle shift 問題問題但,材料特性為質軟、容易起化學變化,但,材料特性為質軟、容易起化學變化,容易吸水有潮解現象,耐候性不佳等問題。容易吸水有潮解現象,耐候性不佳等問題。Curtis19CRA_1C.R.(30)CRA()Chief Ray Angle(CRA)I0IImage plane與CRA有關的參數:1、cos4 Law:I=I0cos42、RI=I/I0 (相對照度)Curtis20CRA_225Sensor端會要求CRA 符合此角度配合micro lens 的調整。(micro lens與sensor的距離,影響CRA需 求的大小)例:SENSOR的CRA要求希望25,A、RI=50 at 30()B、RI=55 at 30()誰優?實裝上,A周邊光亮比B亮,為何?因為,A的CRA()=25;B的CRA()=30A比B能配合SENSOR,故A比B亮。Curtis21