南开大学光学工程内部课件Sep-21st.pptVIP

Lens Lens—Thin-lens equations Lens—Thin-lens equations If the indices of the media at left and right parts of the lens is different, let say n1 and n2, the formula for conjugate point S and P is Lens—Thin-lens equations Finite imagery Thin-lens combinations Lens —Thin-lens combinations Lens —Thin-lens combinations Thin-lens combinations Lens —Thin-lens combinations Analytically, we have for L1: Lens —Thin-lens combinations Because So2=d-Si1, we have: Lens —Thin-lens combinations The total transverse magnification of the compound lens is the production of the individual magnification, that is Lens —Thin-lens combinations Lens —Thin-lens combinations Example Compute the image distance associated with an object 50cm from the first of two positive lenses and its transverse magnification. The two lenses in turn are separated by 20cm and have focal length of 30cm and 50cm respectively. Lens —Thin-lens combinations Lens —Thin-lens combinations Focal length Back focal length fb: the distances from the last vertex of an optical system to the back focal point of the system as a whole. Front focal length ff: the distance from the first vertex to the front focus point. Lens —Thin-lens combinations If there are N thin lens in contact, 球面透镜可否完美成像？ Mirror — Planar mirror Planar mirror Inversions via planar mirror Mirror — Spherical mirror 1 The mirror formula Since ?I=?r, with the help of right figure we have: Mirror — Spherical mirror By using the same sign convention as we did for refraction, we can see So and Si are on the left and therefore positive and negative because C is to the left V. So: Mirror — Spherical mirror In paraxial region, Mirror — Spherical mirror Again the object (or primary) and image (or secondary) focus are defined as Mirror — Spherical mirror 2. Finite imagery The finite imagery properties of spherical mirror are so similar to those of lenses and spherical refracting surfaces. Mirror — Spherica