american optical AO Series User manual

REFERENCE MANUAL
AO
Series
20
Microscope
Advanced
Microstar
and
Phasestar
Models
Price $1.00
@ AMERICAN OPTICAL
? CORPORATION
SCIENTIFIC INSTRUMENT DIVISION ¢ BUFFALO, N.Y. 14215

INSTRUMENT WARRANTY
This
American
Optical
Corporation,
Scientific
Instrument
Division,
product
is
warranted
against
defec-
tive
material
and
workmanship
for
one
year.
This
warranty
applies
only
to
new
products
that
have
not been tampered with or misused in any way.
AO
will
not
be
liable
to
anyone
for
special
or
consequential
damages
of
any
kind.
Nor
does
AO
warrant
consumables
or
accessories
not
manufactured
by
AO.
AO
makes
no
implied
warranties
of
merchantability
or
fitness
for
a particular
purpose.
CLAIMS AND RETURNS
If discrepancies are discovered, an immediate report should be made to the customer’s ordering point
referring to the packing list number. All packing should be carefully examined to insure that no small
items are overlooked. Claims for loss or damage in transit should be made directly to the transportation
company,
If, upon delivery, the outside of the packing case shows evidence of rough handling or damage, the
transportation company’s agent should be requested to make a “Received in Bad Order” notation on
the
delivery
receipt.
If
there
is
no
exterior
evidence
of
rough
handling
upon
delivery,
but
concealed
damage is evident upon unpacking the shipment, within 48 hours of delivery the transportation company
should be requested to make out a “Bad Order” report. This procedure is necessary in order to main-
tain the right of recovery from the carrier.
Customers are requested to write to American Optical Corporation, Scientific Instrument Division,
Buffalo, New York 14215, or their ordering dealer for permission to return any goods to the factory
for
any
reason.
The
letter
of
request
should
indicate
the
date
and
number
of
the
invoice,
or
packing
list. If arrangements are made for a return, the material should be plainly tagged with the customer’s
and/or dealer’s name and address, carefully packed and shipped PREPAID.
PRODUCT CHANGES
The American Optical Corporation, Scientific Instrument Division, reserves the right to change designs
or to make additions to or improvements in its products without imposing any obligations on itself to
add such to products previously manufactured.
The equipment supplied may not agree in all details with our descriptions or illustrations because
instruments are subject to modification and improvement.
SERVICE
Repairs should be performed only by qualified service personnel. Complete repair facilities are avail-
able
at
many
AO
authorized
dealers,
and
AO
Technical
Service
Centers
in
Buffalo,
N.
Y.,
Chicago,
Il, Glendale, Calif., Springfield, N. J., and Dallas, Texas.
TABLE OF CONTENTS
Introduction ...
Preliminary Procedure
Description and Placement of Filters
Eight Filters Supplied .
Filter Placement ............
Identification of Filters ii
Installation of Lamp and Lamp Holder .
Centration of the Lamp 4
Procedure for Brightfield Microscopy ..
Oe UUHROW OW Ww
Procedure for Phase Contrast Microscopy
Care and Cleaning
Lamp
Replacement
.........
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Series 20 Parts List

AO Series 20 Microscope
Advanced
Microstar
and
Phasestar
Models
Figure A
INTRODUCTION
The AO Series 20 Microscope represents well over a
century of American experience in the design and
manufacture
of
fine
microscopes.
The
Series
20
features a research type illuminator with a high in-
tensity, halogen (quartz-iodine) lamp that provides
uniform
intensity
throughout
its
life
at
a
consistent
desirable color temperature of 3200°K.
The two built-in filter turrets are another important
Series
20
feature.
The
Microscope
offers
a
wide
variety
of
preferred
neutral
density,
color
compensating
and
complementary
filters
which
can
be
quickly
positioned
in
the
light
path.
The
high
intensity
illumination
and
the
built-in
filter
turrets
combine
to
make
a
signifi-
cant
contribution
to
the
convenience
enjoyed
by
the
microscopist
and
add
new
instrument
versatility
for
his professional pursuits.
While
this
Reference
Manual
has
been
written
on
the
assumption
that
it is
to
be
used
by
advanced
students
and
experienced
microscopists,
procedural
steps
for
brightfield
and
phase
microscopy
are
outlined
in
considerable
detail,
These
step-by-step
procedures
will
serve
as
a
quick
review
for
the
more
advanced
user
and
will
be
most
helpful
in
the
instruction
and
training
of
those
less
experienced.
With
proper
care,
the
AO
Series
20
Microscope
will
provide
a
lifetime
of
satisfying,
dependable
service.
Should
an
occasional
need
for
service
occur,
the
user
can
readily
contact
competent,
trained
personnel
at
an
authorized
AO
dealer
or
an
AO
Technical
Service
Center.
The
last
section
in
this
Reference
Manual
is
a
Parts
List
for
the
Series
20
with
exploded drawings
keyed
to
parts
listings.
PRELIMINARY PROCEDURE
This
Manual
is
written
as
a
supplement
to
the
Series
10
Microstar Reference
Manual,
10-101.
For
informa-
tion
on
fundamentals
such
as
focusing,
infinity
cor-
rected
objectives,
care
of
the
microscope,
etc.,
read
the
10-101
carefully.
If
a
Series
20
Phasestar
Micro-
scope
has
been
purchased,
the
AO
10
Phase-101
Reference
Manual
has
also
been
supplied
with
the
instrument.
A
review
of
the
Preliminary
Procedure
and
other
sections
of
this
manual
will
be
of
benefit.
Additional
copies
of
the
10-101
and
10
Phase-101
Reference
Manuals,
as
well
as
this
Manual
20A-101,
are
available
at
no
charge
as
an
AO
customer
service.
DESCRIPTION
AND
PLACEMENT
OF
FILTERS
IN
FILTER
TURRETS
The
base
of
the
AO
Series
20
Microstar
Microscope
contains
two
built-in
filter
turrets,
Each
turret
is
de-
signed
to
accept
four
filters
in
addition
to
the
open
aperture.
A
hinged
door
permits
access
to
the
turrets
for
the
insertion
and
removal
of
filters,
To
indicate
which
filters
are
in
the
“in
use”
position,
alphabetical
designations
are
used
with
the
upper
right
hand
turret
and
numerical
designations
with
the
lower
left
hand
turret.
Turrets
can
be
rotated
in
either
direction.
When
the
“O”
designation
on
both
turrets
is
indexed
toward
the
user,
the
open
apertures
of
the
turrets
are
positioned
in
the
light
path
of
the
microscope.
EIGHT FILTERS SUPPLIED
The
four
filters
supplied
for
the
lower
turret
are:
No.
2062
Didymium
Filter,
blue/pink
No.
310-601
Neutral
Density
Filter,
50%
transmission
No.
310-602
Neutral
Density
Filter,
25%
transmission
No.
310-603
Neutral
Density
Filter,
5%
transmission
The
four
filters
supplied
for
the
upper
turret
are:
No. 619 Blue Filter for Polacolor®
No.
2060
Blue
Compensated
Filter,
EK
80A-+CC10R
for
color
transparencies
No.
2061
Green
Filter
for
phase
microscopy
and
black
&
white
photography
No. 406 Blue Filter, daylight
Polacolor® by Polaroid Corporation
cj

FILTER PLACEMENT
The suggested sequence for placement of the filters
into the turrets is the most convenient arrangement
for anticipated general usage. The individual can, if
desired, interchange filter positions or use additional
special filters to best accomplish his own particular
efforts.
Using Figure B as a reference, place the filters in their
respective turret apertures. Begin with the Jower turret
set at “O”, Rotate this turret clockwise until the
aperture between “O” and “1” is most accessible (as
shown in Figure C) and insert the blue/pink Di-
dymium Filter, When inserting, hold the filter by the
edge to keep surfaces clean. (If dust, dirt or a grease
smear is noted on any of the filters, use a soft brush,
lint-free cloth, or cotton and, if required, a mild
detergent solution to clean. Since the No. 2060 filter
(positioned later in the upper turret) is a multi-
layered filter, only slightly moisten surfaces, if neces-
sary, to clean. Keep water or solution away from
filter edges, Should a filter inadvertently be placed in
the wrong aperture, use a toothpick or similar slender
RECOMMENDED POSITIONS OF FILTERS INTO ILLUMINATOR
TURRETS OF SERIES H20 MICROSTAR
#406
BLUE FILTER OPEN
(1.5
mm
thick)
SCO
APERTURE
#310-602
NEUTRAL DENSITY FILTER
25% TRANSMISSION
#310-603
NEUTRAL DENSITY FILTER
5% TRANSMISSION
#310-601
NEUTRAL DENSITY FILTER
50% TRANSMISSION
LOWER TURRET
UPPER TURRET
#2060 BLUE
COMPENSATED FILTER
EK 80A+CCIOR
(GLASS THICKNESS
2.5 mm)
#619
BLUE FILTER
(4 mm thick)
OPEN APERTURE
#2062
DIDYMIUM FILTER BLUE/PINK
(2 mm thick)
Figure B

a
ee
eT
Figure
D
object to push the filter up sufficiently to grasp with
the fingers as shown in Figure D.
Continue rotating the lower turret clockwise going
past the next aperture (used for open aperture) until
the filter position between “2” and “3” is most acces-
sible. Insert the 50% Transmission Neutral Density
Filter. To aid in differentiating between neutral den-
sity filters, remember that the thicker the filter and
the darker the color, the less light the filter transmits,
Thus, the 50% filter is the thinnest and lightest in
color of the three. Continue clockwise positioning the
25% Neutral Density Filter between “3” and “4” and
the 5% between “4” and “0”.
Place the filters in the upper turret in the same man-
ner, starting at “O” and rotating the turret clockwise.
This will place the No, 619 Blue Filter (4mm thick)
between “O” and “A”; the EK 80A+CCIOR Filter (a
multi-layered blue filter with a glass thickness of 2.5
mm) between “A” and “B”; and the Green Filter
between “B” and “C”. The open aperture is next fol-
lowed by the No. 406 Blue Filter (1.5mm _ thick)
positioned between “D” and “O”.
NOTE: Be sure the filters are properly inserted and
fully seated in the turret wells, Remove the
filters,
whenever
the
microscope
is
tran-
shipped or excessively tilted. Keep the filter
turret access door closed to exclude dust.
IDENTIFICATION OF FILTERS IN LIGHT PATH
When using the suggested sequence for filter place-
ment, the numbers and letters on the turrets, when
indexed toward the user, indicate which filters (or
open apertures) are in the light path as follows:
Lower Turret
“O" — Open Aperture
Upper Turret
“O" — Open Aperture
“1
—
50%
Neutral
"A"
—
Blue
Filter,
Density
Filter
daylight
"9"
_
25%
Neutral
“B’’
—
Blue
Filter
for
Density
Filter
Polacolor
"3"
_
5%
Neutral
“C""
—
Blue
Compen-
Density
Filter
sated
Filter,
EK 80A+-CCIOR
"4"
—
Didymium
Filter
—
“D’”
—
Green
Filter
INSTALLATION OF LAMP AND LAMP HOLDER
1. Use the paper wrapper to keep fingers from di-
rectly contacting glass. (Fingerprints and stains will
etch into the quartz lamp and should be removed
with cleaning tissue and alcohol or acetone before
using the lamp.) Insert the No, 2052 lamp into the
socket of the lamp holder. Take care not to force
lamp excessively. Important: The lamp is properly
inserted when approximately 1/8” of the contact
pins remain exposed above the lamp holder socket
plate as illustrated in Figure E.
2. Check to see that the lamp holder locking screw is
turned out sufficiently and insert lamp holder into
microscope base as shown in Figure E. Note that
the holder is positioned so that the diffusing glass
is toward the front of the instrument,
.
Temporarily
tighten
lamp
holder
locking
screw.
4,
Check
to
see
that
the
No,
2051
Variable
Trans-
former
is
turned
off
and
insert
the
3-prong
plug
of
the
lamp
holder
cord
into
the
receptacle
on
the
back
of
the
transformer.
5. Plug the transformer cord into a 115V, 60 cycle
outlet,
Pilot
light
indicates
when
the
transformer
is turned on.
w
CENTRATION OF THE LAMP TO THE OPTICAL PATH
OF THE MICROSCOPE
1, Turn on transformer to the 9 volt setting.
2, Position both filter turrets at “O” (open apertures).
3. Place a piece of white paper or a ground glass over
the light well in the microscope base as shown in
Figure F, Make certain that the paper is flat on the
well.
4.
Partially
close
the
field
diaphragm
by
moving
the
field
diaphragm
lever
to
the
left
until
the
lever
is
approximately
1/2”
from
the
end
of
its
excursion.
. Loosen the lamp holder locking screw with one
hand and simultaneously hold lamp holder with the
wa
CONTACT PINS
DIFFUSING
LAMP HOLDER GLASS
LOCKING SCREW
Figure E

Figure F
other hand as shown in Figure F. Move lamp
holder in or out of microscope base and rotate
holder until the light directed to the paper is
centered in the light well opening. While carefully
keeping the lamp holder in the correct position for
light centration, tighten the locking screw. Remove
paper or ground glass from top of light well.
Lig
AUXILIARY
SWING-IN
CONDENSER
CONDENSER APERTURE
DIAPHRAGM LEVER =
RI
LIGHT WELL
FILTER TURRETS
FIELD DIAPHRAGM
CENTERING KNOBS
cn
PROCEDURE FOR BRIGHTFIELD
MICROSCOPY
. Turn on the transformer to the 9 volt setting.
. Make certain the lamp is centered following the
method entitled “Centration of the Lamp, etc.”
Rotate the upper turret to the “A” setting to po-
sition the No. 406 Blue Filter in the light path.
Rotate the lower turret to “3” for use of the 5%
Transmission Filter. Add Filter #310-602, 25%
Transmission, if light level is too intense for your
purpose.
. Fully open both the field diaphragm of the illu-
minator and the aperture diaphragm of the con-
denser by moving the levers to the extreme right
as shown in Figure G.
. Turn the condenser focusing knob, on the side of
the microscope base as seen in Figure G, counter-
clockwise to the end of its excursion.
. Place a specimen slide on the stage.
. Rotate the microscope objective nosepiece to move
the 10X objective into working position.
. Check to see that the auxiliary swing-in con-
denser, Figure G, (used only with 4X scanning
objective) is out of the light path.
. Raise the microscope condenser by means of the
condenser rack and pinion knob, Figure H. Raise
until the top of the condenser is approximately the
thickness of a piece of paper beneath the slide. In
the event that the top lens of the condenser is
FIELD DIAPHRAGM
LEVER
Figure G

10.
11.
12.
13.
14,
15.
too
far
from,
or
too
close
to,
the
underneath
side
of
the
specimen
slide,
adjust
the
height
of
the
stop
screw
in
the
substage
condenser
assembly
in
accordance
with
the
section
entitled
“Substage
Equipment”
in
Reference
Manual
10-101.
Lower the 10X objective by rotating a coarse ad-
justment focusing knob to its positive stop. Use a
fine
adjustment
focusing
knob
to
bring
the
speci-
men into sharp focus. If necessary, adjust lamp
centration
by
very
slightly
re-positioning
the
lamp
holder, as shown in Figure F, for full, even illu-
mination of the field of view.
Adjust the microscope body for interpupillary
setting
and
eye
difference.
See
section
entitled
“Bodies” in Reference Manual 10-101.
While viewing thru the microscope, partially close
the
field
diaphragm
(move
lever
approximately
1”
to the left as shown in Figure I) so that the iris
diaphragm leaves are imaged within the field of
view.
Bring
the
leaves
into
sharp
focus
by
raising
or
lowering
the
condenser
by
means
of
the
con-
denser rack and pinion knob without disturbing
the fine adjustment knob setting.
Using
the
centering
knobs
on
the
microscope
base,
as
shown
in
Figure
I,
center
the
image
of
the
field
diaphragm
to
the
periphery
of
the
field
of
view.
This
is
best
accomplished
by
rotating
the
two
knobs
simultaneously.
After
centering,
open
the
field
diaphragm
until
the
iris
leaves
“just”
disappear
beyond
the
field
of
view.
Remove
an
eyepiece
and
view
the
back
aperture
of
the
objective
as
shown
in
Figure
J.
Close
the
condenser
aperture
diaphragm
. . .
then
re-open
until
the
iris
diaphragm
leaves
“just”
disappear
from
view
to
obtain
the
full
resolving
power
of
the
microscope.
If desired, the condenser aperture diaphragm may
be closed as required, depending upon the speci-
men, to enhance contrast and depth of focus. It
also
may
be
desirable
to
rotate
the
condenser
focusing
knob,
Figure
G,
very
slightly
clockwise
to
obtain optimum illumination.
When
changing
to
higher
power
objectives,
the
positions
of
the
aperture
and
field
diaphragms
must
be
reset.
As
magnification
increases,
the
aperture
diaphragm
must
be
opened
and
the
field
diaphragm
closed
as
required.
Also
recenter
field
diaphragm
and
refocus
the
condenser
if
necessary.
For
bright,
evenly
uniform
illumination,
readjust
the
position
of
the
condenser
focusing
lens
in
the
microscope
base
with
a
slight
turn
of
the
con-
denser
focusing
knob.
As
specimens
and
instrument
applications
vary,
the
other
turret-mounted
filters
and
transformer
settings
are
used
appropriately.
Additional
neutral
density,
compensating
or
complementary
filters
may
be
inserted
into
the
recessed
light
well
(Fig-
ure
G)
in
the
microscope
base
if
desired.
The
aperture
and
field
diaphragms
should
never
be
used
to
control
light
intensity.
Figure I
Figure J
CONDENSER
(CK & PINION.
“hnos
Figure H
=
te
ae
—
s

Figure K
PROCEDURE FOR PHASE CONTRAST MICROSCOPY
The No. 1240 Phase Turret Condenser and the No.
1246 Single Annulus Phase Condenser are designed
for universal use on both AO Series 20 and Series 10
Microscopes. When using either type phase con-
denser on a Series 20, the bottom (doublet) lens of
the condenser must be removed regardless of whether
the condenser was supplied with a Series 20 or a
Series 10 Microscope.
After removing the phase condenser from the fork
mount of the microscope, unscrew the retaining ring
with the spanner wrench supplied to free and remove
the doublet lens as pictured in Figure L. Save the
Figure L
ring and lens as they are returned to position when
using the condenser with an AO Series 10 Microscope.
When mounting the phase condenser in the fork, be
certain that the slot in the back of the condenser
assembly fully “seats” around the pin in the fork
mount and that the retaining screw is firmly hand
tightened.
If using Series 10 phase accessories to convert a Series
20 Microscope from brightfield to phase microscopy,
a condenser stop extension cap must be attached to the
stop screw in the fork mount. Mounting the condenser
and attaching the extension cap are both illustrated
in Reference Manual 10 Phase-101 under “Operation
of Turret Condenser”.
1. If necessary, withdraw the two annular diaphragm
centering wrenches, Figure M, and rotate the
phase turret condenser to the open aperture. (All
annular diaphragm settings are color-coded to the
phase objectives by colored rectangles on the face
of the knurled ring of the turret condenser. The
10X annulus setting is designated by a green rec-
tangle; 20X by a blue rectangle; yellow, 45X; and
red, 100X.) The open aperture setting has no
designation; therefore; rotate the knurled ring to a
point midway between the red and green
rectangles.

2.
Follow
steps
1
thru
7
under
PROCEDURE
FOR
BRIGHTFIELD
MICROSCOPY
keeping
in
mind
that
a
stained
specimen
slide
is
used
to
ac-
complish
initial
steps
in
the
phase
operating
pro-
cedure
because
an
unstained
specimen
generally
lacks
sufficient
contrast.
3.
Raise
the
condenser
to
its
stop
by
means
of
the
rack
and
pinion
knob,
Figure
H.
The
top
lens
of
the
condenser
should
be
approximately
the
thick-
ness
of
a
piece
of
paper
beneath
the
slide.
In
the
event
that
the
top
lens
of
the
condenser
is
too
far
from,
or
too
close
to,
the
underside
of
the
speci-
men
slide,
adjust
the
height
of
the
stop
screw
(with
extension
cap
attached)
in
the
substage
condenser
assembly
as
shown
under
“Operation
of
Turret
Condenser”
in
10
Phase-101.
ni
a
PHASE
TURRET
CONDENSER
ANNULAR DIAPHRAGM
CENTERING WRENCH
CONDENSER APERTURE
DIAPHRAGM LEVER
‘CONDENSER
CENTERING SCREWS
RECESSED
LIGHT WELL
Figure M
FILTER TURRETS
FIELD DIAPHRAGM.
CENTERING KNOBS.
4.
Using
the
10X
phase
objective,
bring
the
specimen
into
sharp
focus.
Adjust
the
microscope
body
for
interpupillary
setting
and
eye
difference.
If
nec-
essary,
adjust
lamp
centration
by
very
slightly
re-
positioning
the
lamp
holder,
as
shown
in
Figure
F,
for
full,
even
illumination
of
the
field
of
view.
5.
While
viewing
thru
the
microscope,
partially
Close
the
field
diaphragm
of
the
illuminator
(move
lever
approximately
1”
to
the
left
as
shown
in
Figure
M)
so
that
the
iris
leaves
are
imaged
within
the
field
of
view.
Approximately
center
the
diaphragm
to
the
field
using
the
two
centering
knobs
on
the
sides
of
the
microscope
base,
Figures
I
and
M.
Open
field
diaphragm
until
the
leaves
disappear
from
view.
FIELD DIAPHRAGM
LEVER

Figure N
"a
6. To center the condenser, swing the Aperture View-
ing Unit, Figure N, into the optical path of the
microscope (see “Use of the Aperture Viewing
Unit” in Reference Manual 10 Phase-101) or re-
move eyepiece and insert the No. 1265 Phase
Telescope.
Close the aperture diaphragm of the condenser
until the iris leaves are brought into view. Bring
the leaves into focus by moving the knob inside
the Aperture Viewing Unit lever as shown in
Figure O. (Disregard the focus of the phase ring.)
Carefully center the iris leaves of the aperture
diaphragm, as shown in Figure P, to the periphery
of the back aperture of the objective using the
condenser centering screws, Figure M, then open
until the iris leaves “just” disappear from view.
Swing the Aperture Viewing Unit out of the op-
tical path of the microscope by moving the lever
toward the back (lamp end) of the instrument.
Figure O
7. Before final centration of the field diaphragm,
check to see that the specimen is still in focus.
Move the field diaphragm lever to the left so
that the iris leaves are imaged within the field of
view. Raise or lower the condenser by means of
the condenser rack and pinion knob until the
leaves are in sharp focus.
Using the two field diaphragm centering knobs on
the microscope base, as shown in Figures I and
M, carefully center the image of the field dia-
phragm to the periphery of the field of view. This
is best accomplished by rotating the two knobs
simultaneously. After centering, open the field
diaphragm until the iris leaves “just” disappear
from view.
Figure P: Centration of the condenser is accomplished by
centering the image of the aperture diaphragm iris leaves to
the periphery of the back aperture of the objective.
8. After centering the field diaphragm, fully open the
aperture diaphragm. All phase microscopy is
carried out with the aperture diaphragm of the
condenser fully opened because each respective
annular diaphragm has its own built-in optimum
aperture stop.
°
. Place a phase specimen slide on the stage.
10. If necessary, withdraw the two annular diaphragm
centering wrenches, Figure M, and rotate the
knurled ring of the phase turret condenser to the
green rectangle to position the 10X annular dia-
phragm into the light path. Set the upper filter
dial to “A” for use of the daylight Blue Filter or
to “D” for use of the Green Filter. Leave the
lower filter dial set at “3” for the 5% Transmis-
sion Neutral Density Filter.
11. Bring the phase specimen into as good focus as
possible.
12. To center the annular diaphragm to the diffraction
or phase plate (ring) of the objective:
With the phase turret set at “A”, push in the two
annular diaphragm centering wrenches as shown
in Figure @. By turning the wrenches slightly as
they are inserted, you will feel them properly
engage into the centering screws of the centering
mechanism.
Swing the Aperture Viewing Unit into the light
path of the microscope (or remove eyepiece and
insert Phase Telescope). Bring the image of the
annulus of the condenser and the diffraction plate
of the objective into simultaneous sharp focus
using the focusing knob in the lever of the Aper-
ture Viewing Unit.

13.
14.
Adjust
the
annular
diaphragm
centering
wrenches,
Figure
Q,
until
the
annulus
image
is
positioned
concentric
with,
and
is
superimposed
on,
the
dif-
fraction
plate
as
shown
in
Figure
R.
After
center-
ing,
swing
out
the
Aperture
Viewing
Unit.
Bring
the
phase
specimen
into
sharp
focus.
The
microscope
is
now
ready
for
use
with
the
10X
objective.
To
center
other
annuli
to
their
respective
phase
objectives
and
for
technique
with
higher
magni-
fication
objectives,
refer
to
the
last
two
steps
under
“Optical
Alignment
Procedure”
and
“Gen-
eral
Comments
on
Technique”
in
10
Phase-101.
As
specimens
and
instrument
applications
vary,
the
other
turret-mounted
filters
and
transformer
settings
are
used
appropriately.
Additional
neutral
density,
compensating
or
complementary
filters
may
be
inserted
into
the
recessed
light
well
(Fig-
ure
M
)
in
the
microscope
base
if
desired.
The
No.
308
Heat
Absorbing
Filter
is
recommended
for
light/heat
sensitive
specimens.
The
aperture
and
field
diaphragms
should
never
be
used
to
control
light
intensity,
Figure Q
Figure
R
—
Appearance
of
the
image
of
the
annulus
and
the
diffraction
plate
of
the
objective
when
annulus
is:
(A)
out
of
center;
and
(B)
concentiic
with,
and
properly
superimposed
on,
the
diffraction
or
phase
plate.
CARE AND CLEANING
Refer
to
the
section
entitled
“Care
of
the
Microscope”
in
Reference
Manual
10-101
for
a
comprehensive
description
of
cleaning
procedures.
Also
refer
to
the
copy
on
cleaning
in
section
entitled
“Filter
Placement”
under
PRELIMINARY
PRO-
CEDURE
in
this
Manual.
LAMP REPLACEMENT
When
replacing
the
lamp,
make
certain
that
the
lamp
previously
in
use
has
cooled
sufficiently
to
handle.
Insert
the
new
lamp
in
the
manner
described
in
“Installation
of
Lamp
etc.”
under
PRELIMINARY
PROCEDURE.
To
order
replacement
lamps,
see
Parts
List,
page
20.

Figure
S:
Pictured
on
the
above
left,
the
No.
1053A
35mm
Camera
shown
with
the
5X
Adapter.
The
No.
1057
Shutter,
Cable
and
Lens
Assembly
has
a
2.8X
and
5X
position
lever.
Pictured
on
the
above
right,
the
No.
1052A
Polaroid
Land
Camera
which
utilizes
the
3-1/4”
x
4-1/4”
Polaroid
Land
film
pack,
The
No.
1055A
Camera
Back
Adapter
(not
illustrated)
accepts
4”
x
5” Polaroid
Land
film.
EXPOSURE TABLES FOR SERIES H20 Microstar
Models with AO Catalog No. 1052A, 1053A, and 1055A Cameras
General photomicrographic technique with a Series
H20 Microscope is the same as with a Series L10
except that selected filters in the built-in, filter turrets
are utilized. Also with a Series H20 Microscope, faster
exposure times are used because of the high intensity,
halogen lamp. The exposure tables in this manual are
predicated on the use of stained specimens of average
density. (As a guide, phase specimens require ap-
proximately 10 times more exposure.) The variable
transformer is set at 12 volts for photomicrography;
however, use the 9 volt setting while making prepara-
tions to take photomicrographs to assure longer lamp
bulb life.
With Kodachrome II Film and black and white
Polaroid Type 107 Land Film, note that three filters
are required. If extra, loose filters are not available,
remove the 25% Transmission Neutral Density Filter
from the lower filter turret and insert into the recessed
light well in the microscope base. For removal of this
filter, refer to “Filter Placement” under PRELIMI-
NARY PROCEDURE in this manual. If your Series
20 Microscope is used extensively for photomicrog-
raphy, an extra set of Neutral Density Filters, AO
Catalog No. 310, can be purchased.
Review the sections entitled, “Description” and “Set
Up and Use” in Photomicrographic Equipment
Reference Manual 1052-101. A complimentary copy
of this manual is available upon request.

EXPOSURE
TABLES
FOR
SERIES
H20
MICROSTAR
1. 35mm. Films
A.
EK
Kodachrome
II
B.
EK
Panatomic
X
ASA
-
25
ASA
-
40
Filters
-
#2060,
EK
80A/CCIOR
Filters
-
#2061,
Green
#2062,
Didymium
#310-601,
Neutral
Density,
#310-602,
Neutral
Density,
50%
Transmission
25i/esTconsmission
Transformer
-
12
volt
setting
Transformer
-
12
volt
setting
Shutter
Speed
Shutter
Speed
Objective
Objective
2.8X
Position
5X
Position
2.8X
Position
5X
Position
4X
1/125
1/50
4x
1/50
1/25
10X
1/50
1/25
10x
1/50
1/25
20x
1/50
1/25
20x
1/50
1/25
4OX,
45X
1/25
1/10
40X,
45X
1/25-1/10
1/10
100X
1/10
1/5
100X
1/10-1/5
1/5
Il. Polaroid Land Film
A. Polacolor Types #108, 58
ASA - 75
Filters - #619, Blue
#2062, Didymium
Transformer - 12 volt setting
Lens and Shutter Assembly Lever -
set at 5X position
| B. Black & White Type #107
ASA - 3000
Filters - #2061, Green
#310-602, Neutral Density,
25% Transmission
#310-603, Neutral Density,
5% Transmission
Transformer - 12 volt setting
Lens and Shutter Assembly Lever -
set at 5X position
Shutter
Speeds
Shutter
Speeds
Objective
Objective
[aarxan”
wus”
3%"
x
ava”
aus"
AX
1/50-1/125
1/50
4x
1/125
1/125
10x
1/50-1/125
1/50
10x
1/125
1/125
20x
1/50-1/125
1/50
20x
1/125 1/125
A5X
1/25
1/10
40X,
45X
1/25-1/50
1/25
100x
1/10
1/5
100X
1/10-1/25
1/10

Figure T
Figure T: When using the No. 1050 Viewing Screen
on a Series 20 Microscope, the No. 2051 Variable
Transformer is generally set at 12 volts and the use of
a Neutral Density Filter is not required, Resultant
magnification at the screen plane is 7.5 times the
initial magnification of the objective and the field of
view is the same as through 10X wide field eyepieces.

PARTS LIST
The Series 20 Parts List in this Reference Manual
is a supplement to the Parts List in Manual
10-101. When a part is desired for a unit common
to
both
Series
10
and
20
Microscopes,
such
as
a
body or stage, use the 10-101 Parts List.
The illustrations are used to identify and locate
parts of the microscope, and are keyed to the
parts
lists
by
the
use
of
index
numbers.
To
order
a part, identify and locate the part by using the
illustrations. Note the index number for the part
and cross-reference it to the parts list. The part
number,
description,
and
quantity
required
will
be found opposite the index number.
In certain cases, it may be desirable to replace a
complete assembly instead of overhauling or re-
building with detail parts. Where complete as-
semblies are available, they are indicated by a
note in the description column to show which
parts they include. Detail parts of these assemblies
are also available separately.
Parts or assemblies should be ordered directly
from AO’s Instrument Division plant at Buffalo,
N.Y., or from any of AO’s authorized dealers.
When ordering parts, be sure to include a com-
plete description, part number, and correct
quantity.
SERVICE
Complete repair facilities are available at many of AO’s authorized dealers, the American Optical
Corporation, Scientific Instrument Division plant, Buffalo, N.Y., and AO Technical Service
Centers in Chicago, Ill., Glendale, Calif., Springfield, N.J., and Dallas, Texas.
Arm Assembly
(See Reference
Manual 10-101)
Base Assembly
(See Figure 2)
Lamp Housing
(See Figure 3)
Figure
1.
Series
20
Microscope
Stand
&
Lamp
Housing

Figure 2. Base Assembly
Part
Index
No.
Number
Description
Quantity
20-859
Base
Assembly
1
1
20-16
Knob
2
2
X-20599
Screw,
Set
2
3
20-17
Bearing
2
4
20-14
Shaft
2
5
20-6
Screw,
cover
2
6
X-51346
Washer,
spring
4
7
20-501
Base
Assembly
(Includes
item
8)
1
8
20-5
Cover
a
9
20-8
Pin,
lock
2
10
20-7
Plate,
lock
1
20-864
Condenser
Assembly
(Includes
items
11,
12,
1
and 18)
11
20-44
Ring,
retaining
1
12
1084-612
Lens,
back
(aspheric
surface
toward
#11)
1
13
20-63
Body,
condenser
1
14
20-42
Pin,
guide
1
15
20-43
Pin,
guide
1
16
X-38004
Screw
2
17
20-41
Rack
1
18
20-39
Shaft,
pinion
1
19
X-51404
Ring,
retaining
1
20
20-40
Bearing
1
21
1062-76
Washer,
spring
1
22
X-20598
Screw,
set
1
23
20-38
Knob,
condenser
1
24
X-16336
Washer,
lock
2
25
X-
19526
Screw
2
20-853
Cell
Assembly
(Includes
items
26,
27,
28,
1
and 29)
26
20-59
Ring,
retaining
3
27
20-603
Glass,
heat
absorbing
1
28
20-23
Cell
1
29
20-601
Lens,
collector
1
30
01163
Washer
1
31
X-20108-58
Screw
2
32
X-19965
Screw
2
33
20-851
Iris
Diaphragm
Assembly
1
34
20-863
Lever
1
35
20-35,
Screw,
pivot
1
20-861
Base
Cover
Assembly
(Includes
items
36, 38,
1
39 and 40)
36
20-31
Cover,
base
1
37
X-34140
Screw
6
38
X-51771
Bumper
4
39
X-16015
Washer
6
40
X-8015
Nut
4
20-857
Mirror
Assembly
(Includes
item
41
and
1
Mirror
Mount
Assembly
20-854)
41
20-602
Mirror
1
20-854
Mirror
Mount
Assembly
(Includes
items
4,
6,
1
39, and 42 thru 53)
42
20-21
Pin,
short
pivot
1

Figure 2. Base Assembly (Cont. )
Part
Index No. Number Description Quantity
43 20-25 Bracket 1
44 X-20588 Screw, set 2
45 20-15 Eccentric 2
46 20-13 Spacer 2
AT 20-18 Plate, swivel af
48 20-12 Spring aL
49 20-22 Pin, spring a
50 X-51404 Ring, retaining 1
51 X-25361-58 Screw, set 2
52 X-8078 Nut 2
53 20-20 Pin, long pivot 1
54 X-26118 Screw 2
55 X-16010 Washer, plain 2
56 01551 Pin 2
57 20-26 Screw, shoulder 2
58 20-30 Spring, detent 2
59 20-28 Holder, right hand wheel 1
60 20-29 Wheel, detent 2
61 X-51327 Ring, retaining 1
62 1036-606 Window 1
63 20-27 Holder, left hand wheel 1
64 20-11 Bearing, disc 2
65 X-51775 Washer 2
66 20-9 Turret, right hand filter (upper) 1
67 20-10 Turret, left hand filter (lower) 1

Figure 3. Lamp Housing
Part
Index
No.
Number
Description
Quantity
i
20-50
Spacer
8
2
20-53
Fin
6
3
20-54
Fin
al
4
X-8010
Nut
1
5
X-16010
Washer,
plain
1
6
20-52
Chimney
1
a
X-285
Screw
1
8
X-38120
Screw
6
9
20-55
Deflector
1
10
20-51
Baffle
1
11
X-16020
Washer
-
eliminated
September
1970
1
12
X-8040
Nut
-
eliminated
September
1970
1
13
X-38001
Screw
2
14
20-48
Cover,
Lamp
Housing
1
15
20-852
Clamp
Screw
Assembly
1
16
X-38036
Screw
2
17
20-56
Baffle,
bottom
1
18
X-32571-22
Screw
2
19
20-83
Fiber
Spacer
2)
20
20-46
Lampholder
Support
1
21
20-70
Insulator
Shield
-
modified
Sept.
1970
1

@Am_ERICAN OPTICAL
ss CORPORATION
SCIENTIFIC INSTRUMENT DIVISION * BUFFALO, N.Y. 14215
20A-101
3/73
Printed
in
U.S.A.
“
'P