应用光学ch26-27.ppt

1、Review:,Equation Of Image And Object Positions,或,The lateral magnification:,(2.15),Cardinal Points(基点) Of An Optics System,1. First and second principal planes(物方主平面和像方主平面),2.The First And Second Focal Points（物方焦点和像方焦点）,1. First and second principal planes(物方主平面和像方主平面),Conjugate planes,the first pri

2、ncipal point物方主点,the second principal point 像方主点,the first principal plane,the second principal plane,物方主平面,像方主平面,2.The First And Second Focal Points（物方焦点和像方焦点）,F,-f,the second focal point(像方焦点),the first focal point(物方焦点),the second focal plane(像方焦平面),the first focal plane(物方焦平面),efl,efl,The proper

3、ties of the focal point and plane,F,Fig.2.17,(1) A bundle of parallel rays which have a slope angle with the axis will intersect at one point on the second focal plane after passing through the optical system,(2)Any incident light ray which is parallel to the system axis, will pass through the secon

4、d focal point F,F,Any incident light rays emitted from an object point B which is on the first focal plane off the axis will be a bundle of parallel rays, and the parallel rays have a slope angle with the axis,(2) Any incident light ray which passes through the first focal point will be parallel to

5、the system axis after passing through the optical system,2.6 principal planes and focal points of a single refracting surface,2.6.1 the location of principal points of a single refracting surface,According to the properties of principal planes, they are a couple of conjugate points H and H whose lat

6、er magnification is equal to 1.,Since they are a couple of conjugate planes, the locations of principal points H and H, should meet the requirement of Eq.(2.12),Multiply ll on both sides of the above equation.,We can draw a Conclusion: The two principal points H and H of a single spherical surface a

7、re just at the vertex of the spherical surface. That means the first and second principal planes coincide with(与相互重合)the tangent plane crossing the vertex of the surface, as shown in Fig.2.20.,*单球面的主点和球面的顶点重合 主平面是过顶点的切平面,2.6.2 Focal points of A Refracting Surface,We know the locations of principal p

8、oints and if we can find out the focal lengths, then the locations of the focal points can be determined. According to the definition the back effective focal point (F) is the conjugate image point of the infinite object point.,In Sec.2.6.1 we get the conclusion that the principal points of a spheri

9、cal surface are just at the vertex point of the surface, thus the focal lengths are the distances from the vertex of the surface to the focal points.,Above equations are the focal length formula of a single refracting spherical surface. For the condition of reflection, since a reflection can be take

10、n as a refraction just as if n=-n, we can get,2.7 Principal planes and focal points of a coaxial(共轴的)spherical system,According to the properties of the second focal point F, any ray which is parallel to the axis will get across the second focal point F after passing through the optical system.,So t

11、hat we can calculate a paraxial ray which is parallel to the axis by using the paraxial ray tracing formula, the intersection point of the ray after passing through the system and the axis will be the second focal point.,Eqs.(2.2) to(2.5)or(2.7) to(2.10),f ?,In triangle BHF,BH=BH=h1,FFL(物方顶截距,lF): 前截距,第一面的顶点O1到F的距离 BFL(像方顶截距,lF):后截距,最后一个面顶点OK到F的距离,EFL: the effective focal length, f, f ,Assignment ：,Whats the EFL, FFL and BFL of the negative lens?,Chart Illustration,F,F,H,H,EFL(- F),EFL(+ F),BFL(-