Question

(10 pts) Two thin lenses form a compound lens system. The two lenses have focal length fl = 7.5 cm and f2 = -7.5 cm respectively, and are separated by d = 5 cm. The lenses are in air. (a) Use only pen and ruler to find the positions of the two nodal points N1 and N2. ( Un ) (b) Calculate the position of the two nodal points Nland N2.

for (a) you just need to draw, you don't need to figure it out for N1 and N2

Answer 1

(9) Becaus medium iş airy so on both sides of optical hedel loints System Coincide culth Principal point Front e P P2 ! Ni nodal NI Point = NE? J N₂ back - hodal point If medium to Same on both sides of optical system nodal points are Cancide with principal point Headal points are conjugete looints haning angular magnification is Scanned with CamScanner

pfi- 7.5cm given / (b) Calculation position of two modal boinks CN,Na) == € + tree L -250m given but the natues of fit and fizid we get combined focal length 35cm 3 = 65+C#s)- .531-7.5) ts st5364-5) É 5 F2 56.25 TF1155 cm] Position of Ist hodal point Noz Ed fa 11.2575 25 -7.5 3-7,5 cm -7.5 position of Second nodal boint N2 = - 11.2545 Scanned with CamScanner 5625 2 7:5 . 7.5 em -