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APPENDIX
I
ANSWER KEY TO PROBLEM SETS
Chapter 1
(2) For pancreatic ascinar cells, cell diameter 10 m, nucleus diameter 5 m; secre-
tory granule 1 m. (3) The field stop diaphragm is used to limit the area of illumina-
tion in the specimen to protect the specimen and reduce the amount of scattered light
reaching the eye or detector. Opening the diaphragm too far causes unnecessary expo-
sure and reduces contrast; closing the diaphragm too far masks field of view. Neither
operation changes the intensity of light in the image to a significant extent. The con-
denser diaphragm likewise has an optimum setting, typically allowing transmission
through 70% of the back aperture of the objective lens. A Bertrand lens is required to
make the adjustment. If opened too far, excess light fogs the image; if stopped down,
contrast is improved, but spatial resolution is compromised. The 70% position offers a
good compromise between image contrast and resolution. Reduction of image bright-
ness should be made by reducing the voltage of the power supply or by inserting a neu-
tral density filter in the optical path.
Chapter 2
(1) The principal complementary color pairs are red-cyan; yellow-blue; green-magenta.
Chapter 4
(1a) No, the object is located slightly outside the focal length of the objective. To pro-
duce a magnified real image, the object is located between 1 and 2 focal lengths.
(1b) No, the intermediate image is located slightly inside the focal length of the ocular
as is required to form a magnified virtual image. (1c) The eye-brain system perceives a
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