5-11
SEL200600G
5-2-2. Optical Axis Check
Checking Procedure
1. Adjust the optical axis while observing the microscope until the
chart image can be seen in the center.
2. Perform steps (1) to (6) and check that the AS and CB values are
within specifications.
AS (Astigmatism):
The phenomenon where the flare on the ring chart appears in a
cruciform shape with the ring chart in the sharpest focus. (Fig. a)
(1) Turn the focusing knob until the flare becomes minimum
between two approximately opposite points on the ring
chart edge (as shown with the arrows in Fig. b), and then
read the dial gauge value. <A>
(2) Turn the focusing knob until the fl are becomes minimum
between two points with the phase of the fl are rotated by 90
degrees from the above step (1) condition (as shown with
two arrows in Fig. c), and then read the dial gauge value.
<B>
(3) Calculate the AS value (absolute diff erence between <A>
and <B>) and check that it is within the specifi cation.
AS value = <A> − <B>
(1)
(1)
(2)
(2)
AS
(Fig. a)
(Fig. b)
(Fig. c)
CB (Center Blur):
The phenomenon where the flare on the ring chart trails in one
direction with the ring chart in the sharpest focus. (Fig. d)
(4) Turn the focusing knob until the ring chart edge in the direc-
tion of the maximum fl are is in the sharpest focus (as shown
with the arrow in Fig. e), and then read the dial gauge value.
<C>
(5) Turn the focusing knob until the ring chart edge, opposite
180 degrees from the above step (4) condition (as shown
with the arrow in Fig. f) is in focus, and then read the dial
gauge value. <D>
(6) Calculate the CB value (absolute diff erence between <C>
and <D>) and check that it is within the specifi cation.
CB value = <C> − <D>
(5)
(4)
(Fig. d)
(Fig. e)
(Fig. f)
CB
Specifi cation (Reference):
WIDE
TELE
AS (Astigmatism) 0.10 mm or less
0.12 mm or less
CB (Center Blur)
0.15 mm or less
0.17 mm or less
3. If the specifications of AS and CB are not satisfied, perform the
“5-2-3. Optical Axis Adjustment (B06 frame assy) (Wide)” or
“5-2-4. Optical Axis Adjustment (B01 assy) (Tele)”.
5-2-3. Optical Axis Adjustment (B06 frame assy)
Optical Axis Adjustment (B06 frame assy) is done by increasing
or decreasing the thickness of the washer.
Refer to “2-2. DISASSEMBLY”, disassemble the lens, and
change the thickness of the washer.
Adjusting Procedure
1. Remove the 4 group block, referring to the “2-2. DISASSEM-
BLY” and peel off the adhesive of the B06 frame assy.
2. Remove the three screws fixing the B06 frame assy, and remove
the B06 frame assy.
B2 washer
B06 frame assy
3. Align the marking position and install the B06 frame assy without
inserting the B2 washer.
marking
marking
– Continued on next page –
SYS SET
2019/06/28 22:04:56 (GMT+09:00)
