Olympus IX2 RFAEVA2 - Manual (Page 17)

14
IX2-RFAEVA-2
Explanation Diagrams (Laser Beam Incidence Angle Adjustment)
Explanation 1 : Condition before laser incidence angle adjustment
Glass
· The laser beam is transmitting through the
glass and specimen.
Monitored image
· The fluorescence image of specimen is observed even
when it is defocused by moving the objective upward.
Explanation 2 : Critical angle condition
· The laser beam travels on the upper surface of the glass. · The image flows in the horizontal direction (also in the
vertical direction depending on the camera installation ori-
entation).
Explanation 3 : Total internal reflection condition
· When total internal reflection is achieved, the reflected
laser beam returns to the objective and forms an eva-
nescence field on the glass.
· The image darkens
suddenly.
· The focused plane
is thin.
· The fluorescence image of specimen becomes invisible
when it is defocused by moving the objective upward.
Explanation 4 : Condition before laser incidence
· The laser beam hits the inner frame of objective and
does not reach the specimen.
Specimen
Immersion oil
Objective
Laser beam
Field iris diaphragm
image
Fluorescence image
of specimen
· The image is
completely dark.
· When the camera gain is increased, vague light may be
visible due to the stray light.