Olympus U-UCD8A Gebruiksaanwijzing - Pagina 11

Blader online of download pdf Gebruiksaanwijzing voor {categorie_naam} Olympus U-UCD8A. Olympus U-UCD8A 40 pagina's. Motorized universal condenser

Aperture iris

diaphragm

image

Objective pupil

Fig. 1

Field Iris Diaphragm

70-80%

{The field iris diaphragm controls the size of the illuminated

30-20%

area. By stopping down the field iris diaphragm, in accordance

with the objective in use, until its image circumscribes the

field of view, stray light can be reduced, which in turn increases

the definition and contrast of the image.

Aperture Iris Diaphragm

{The aperture iris diaphragm controls the numerical aperture

(N.A.) of the illuminator. In order to achieve the optimum objec-

tive performance, the opening of the aperture iris diaphragm

should be matched with the N.A. of the objective in use. This

will result in better image contrast and resolution as well as

increased depth of focus.

{As microscopic specimens are usually low in contrast, reduc-

ing the diaphragm opening to 70% or 80% of the objective's

N.A. will generally provide an image of acceptable quality. To

check the opening, after completing focus adjustment, remove

one of the eyepiece lenses and look into the empty eyepiece

sleeve. As you stop down the aperture iris diaphragm, the iris

diaphragm image can be seen in the objective pupil. (Fig. 1)

U-UCD8A