(a) Table 1 lists the Abbé numbers of several different types of glasses. Select the appropriate materials from table 1

[answerhappygod]

A Table 1 Lists The Abbe Numbers Of Several Different Types Of Glasses Select The Appropriate Materials From Table 1 1 (94.88 KiB) Viewed 23 times

(a) Table 1 lists the Abbé numbers of several different types of glasses. Select the appropriate materials from table 1 in order to minimize the overall thickness of an achromatic doublet which has an overall focal length of 20cm and calculate the individual focal lengths of the two touching lens elements used in the doublet. [8 marks] (b) Calculate the focal length and the radii of the first 3 Fresnel zone plates of the diffractive element that can be used with a LF5 Light Flint glass lens in order to achieve achromatic performance around the wavelength of the d Fraunhoffer line (587.56 nm) and the hybrid compound lens has an overall focal length of 20 cm. [9 marks] (c) If the 20cm focal length lens has a diameter of 1 cm, calculate the radius of the diffraction limited Airy disk for blue light (480nm wavelength). Suppose this lens is used to focus an image on a CMOS sensor which covers a rectangular area of 8mm (horizontal) x 6 mm (vertical). Calculate the minimum number of pixels along the horizontal and vertical axes of the CMOS sensor if no anti-aliasing filter is used and spatial aliasing is to be avoided. [8 marks] Abbé Number 17.5 Glass S-NPH3 Lanthium Dense Flint glass SF10 Dense Flint Glass LF5 Light Flint Glass N-LAK7 Lanthium Crown Glass FCD1 Phosphate Crown 28.4 40.85 58.52 81.6 Table 1 Abbé number of different types of glasses