Return to Fig. 12.8 and the broad quasimonochromatic slit source. How wide should this source be if the fringe visibility is to be 0.9? The source is 1.0 m in front of the aperture screen and λ̅₀= 550 nm. The aperture slits are separated by 0.20 mm. You might want to look at Table 1 in the back of the book. What€™s the sinc of Ï€/4?]

 Fig. 12.8

S". (a) (b) (c) (F) AM (e)