BestScope BS-2041B User manual

Biological Microscope
BS-2041B/T
Instruction Manual
BS-2041B BS-2041T
This manual is for biological microscope Model BS-2041B/T. To ensure the safety, obtain optimum
performance and to familiarize yourself fully with the use of this microscope, it is strongly
recommended that you study this manual thoroughly before operating the microscope.

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CONTENTS BS-2041B/T
CONTENTS……………………………………………………………
1
USER NOTICES……………………………………………………
2
1 Components Name ………………………………………………
3
2 Assembly …………………………………………………………
4
2.1 Assembly Diagram ………………………………………………
2.2 Assembly Procedures ……………………………………………
4
5
3 Adjustment ………………………………………………………
9
3.1 Adjustment Set Diaphragm…………………………………………
9
3.2 Adjustment Procedures ……………………………………………
11
4 Technical Specifications …………………………………………
14
5 Outfit………………………………………………………………
15
6 Trouble Shooting…………………………………………………
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USER NOTICE BS-2041B/T
I. Safety Note
1. Open the box carefully to avoid the accessories, like lens, dropping to ground or being damaged.
2. Do keep the instrument out of direct sunlight, high temperature or humidity, dusty and easy
shaking environment. Make sure the stage is flat, horizontal and firm enough.
3. When moving the microscope, carefully carry it with the handle and the base.
4. When running, the lamp house and nearby parts will be very hot. Please ensure there is enough
cooling room for them.
5. Make sure the instrument is earthed, to avoid lighting strike.
6. For safety, be sure the main switch is in “O”(off) state and cut off the power supply before
replacing the bulb or the fuse. If you replace the bulb during use or right after use, allow the
lamp bulb and the lamp house to cool completely before touching.
(Designated bulb：6V/20W Halogen Lamp)
7. Check the input voltage: be sure the input voltage which is signed in the back of the microscope
is consistent with the power supply voltage, or it will bring a serious damage to the instrument.
8. Always use the power cord provided by BestScope.
II. Maintenance and Care
1. All the lenses have been adjusted properly; do not dismount them by yourself please.
2. The nosepiece and coarse and fine focusing parts are so delicate that it is forbidden to
disassemble them carelessly by yourself.
3. Keep the instrument clean, and do not pollute the optical element when wiping away the dust
on the instrument.
4. The contaminations on the prism, like fingerprints and oil smudges, could be gently wiped with
a piece of soft cloth or tissue paper, gauze which has been immersed in pure alcohol or ether.
(Note that the alcohol and ether are highly flammable, do keep them away from the fire or
potential sources of electrical sparks, and use them in a drafty room as possible as you can.)
5. Do not attempt to use organic solvents to clean the microscope components other than the
glass components. To clean them, use a lint-free, soft cloth slightly moistened with a diluted
neutral detergent.
6. When using, if the microscope is splashed by liquid, cut off the power at once, and wipe away
the splash.
7. Do not disassemble any parts of the microscope, as this will affect the function or reduce the
performance of the microscope.
8. Place the instrument in a cool, dry position. When not using the microscope, keep it covered
with a dust cover. Make sure the lamp socket is cool before covering the microscope.

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1.Components Name BS-2041B/T
Eyepiece
Binocular viewing head
Nosepiece
Objective
Main body

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①
②
BS-2041B/T
2 Assembly
2-1 Assembly Diagram
The following figure shows the installation sequence of the components. The number in the figure
shows the assembly steps.
Before installing, be sure every components is clean, do not score any parts or glass surface.
Keep well with hexagon wrench provided. When changing the components, you will need it again.
Main body
Objective
Binocular
viewing head
10X Eyepiece
④
③
Power cord

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BS-2041B/T
2.2 Assembly Procedure
Fig.1
Fig.3
Fig.2
2.2.1 Installing binocular viewing head
(Fig.1-2)
Insert the binocular viewing head into the
microscope head and turn it to a proper
position, then screw down the bolt to fix it.
2.2.2 Installing the eyepiece (Fig3-4)
Insert the eyepiece into the eyepiece tube
until they are against each other, as shown
in Fig.4.
Fig.4

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BS-2041B/T
Fig.6
Fig.5
Fig.7
2.2.3 Installing the objective (Fig.5-6)
1. Adjusting the coarse focus knob until the
support device of the mechanical stage
reaches its low limit position.
2. Screw the lowest magnification objective
into the nosepiece from the left or the right
side, then revolve the nosepiece clockwise
and mount other objectives by the
sequence of low to high magnification
Installing objective this way will make the
change of magnification to be easier during
using.
Clean the objective regularly, for lens is
susceptible to dust.
When operating, use 10×magnification
objective to search and focus specimen
firstly, then replace with higher
magnification objective if necessary.
When replacing the objective, slowly turn
the nosepiece until you hear “clicked”,
that means the objective is in place.
.2.4 Mounting the filters (Fig.7)
1. Place the required filter in front of the
condenser.
★the filter of the standard outfit is green and
baby blue.

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BS-2041B/T
2.2.5 Connecting the Power Cord
(Fig.8-10)
★The cable and cords are vulnerable when
bent or twisted, never subject the power cord
to excessive force.
1. Set the main switch① to “O” (off) state
before connecting the power cord.
2. Insert the plugs② into the power jack
③of the microscope safely.
3. Plug the power cord④into the power
supply receptacle⑤. Make sure the
connection is well.
★Do use the supplied power cord all the
time. If lost or damaged, select the same
standard cord, please.
★A wide range of voltage, like 100V～240V,
is acceptable for this microscope.
2.2.6 Replacing the fuse (Fig.8-10)
Do remember to set the main switch①to
the state “O” (OFF) and unplug the power cord
before replacing the fuse. Rotate the fuse⑥
out of the holder⑦with the “--”type
screwdriver, replace with a new fuse, then
rotate it back to the holder again.
Fig.8
Fig.9
Fig.10

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Fig.11
BS-2041B/T
Fig.12
2.2.7 Installing and Replacing the bulb
(Fig.11-13)
Please use the specified halogen Lamp
6V20W.
1. Pull out the condenser holder as shown in
Fig.11.
2. Hold the bulb①after you wrap it with
gauze or other protection materials, and
then insert its pin②deeply into the jack
in the lamp holder.
3. During microscope using or soon after it is
turned off, the bulb, the lamp house and
nearby parts will be very hot and will
cause serious burns. Please turn the main
switch to “O” (off) and disconnect the
power plug, and make sure the bulb, the
lamp room and periphery are all cool.
Then, you can do your replacing.
Insert the bulb gently. Squeezing too hard
will damage the bulb.
To prevent reduced bulb life or cracking, do
not touch the bulb with bare hands. If
fingerprints are accidentally left on the
bulb, wipe the bulb with a soft cloth.
4. Place the condenser holder back and
press fit.
Fig.13

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3. Adjustment and operation BS-2041B/T
3.1 Adjustment set diagram (Fig.14-15)
Right Fine Focus Knob
Right Coarse Focus Knob
Tension Adjustment Collar
Main Switch
Portrait Adjustment Knob
Lateral Adjustment Knob
Brightness Adjustment Knob
Fig.14

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BS-2041B/T
Left Coarse Focus Knob
Interpupillary Distance Indicator
Fig.15
Clocking Set
Condenser Focusing Knob
Left Fine Focus Knob
Aperture Iris Diaphragm Collar
Indicator

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BS-2041B/T
3.2 Adjustment and Operation
3.2.1 Brightness Adjustment (Fig.16)
1. Connect the power cord and set the main switch
to “－”state (ON).
2. Turning the brightness adjustment knob
clockwise, the voltage raise, and the brightness
strengthen; whereas turning at the contra
direction, the voltage decline, and the brightness
weaken.
2.TUsing the microscope with low voltage in the
voltage range can prolong the service life of the
bulb.
3.3.2 Placing the Specimen (Fig.17)
1. Place the specimen① in the center of the
mechanical stage and use the stage clips to clamp it.
2. Turn the portrait and lateral adjustment
knob②of the mechanical ruler, move the specimen
to the required position.
Be careful when changing the objective. If you
finish the observation with the short working
distance objective, and want to change another one,
be careful of not letting the objective touch the
specimen.
3.3.3 Focusing the Specimen (Fig.18)
1. Focus the specimen with 10X objective. To avoid
the objective touching the specimen during
focusing, you should raise the mechanical stage to
let the specimen close to the objective at first, then
slowly separate them to bring the specimen to
focus.
Fig.16
Fig.18
Fig.17

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BS-2041B/T
Turn the coarse focus knob ①conversely to
lower the specimen and search images in the
10×ocular simultaneously, and then use the fine
knob②to focus. After that, you can replace with
other magnification objectives safely, and focus
without the risk of damaging the specimen.
To make the observation more convenient, you
can use the locking set③ to fix the stage in a
vertical direction.
3.3.4 Condenser Adjustment (Fig.20)
Turn the condenser focus knob to move the
condenser up and down. Raise the condenser when
using the high magnification objective, and descend
it when using the low magnification one.
The condenser and the objective are coaxial. It
has been adjusted before leaving factory, so the
user needn’t to adjust them by self
The highest position of the condenser has been
adjusted too. It also needn’t any user’s
operation.
3.3.5 Aperture Iris Diaphragm Adjustment
(Fig.20)
Turn the aperture iris diaphragm collar① to
adjust the aperture iris diaphragm.
The aperture iris diaphragm is designed for
the adjustment of the numerical aperture, not for
the brightness.
Generally, setting the aperture iris diaphragm to
70- 80% of the N.A. of the objective in use will
provide an image with good contrast. If you want to
observe the image of the aperture iris diaphragm,
remove one eyepiece and look through the tube.
You will see a dark circle encroaching on the bottom
of the tube.
Fig.19
Fig.20

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BS-2041B/T
3.3.6 Adjusting the Interpupillary Distance
(Fig.21)
The interpupillary distance range:
55mm～75mm。
While looking through the eyepieces, move both
eyepieces until the left and right fields of view
coincide completely.
3.3.7 Adjusting the Diopter (Fig.22)
1. Turn the eyepiece①to adjust the diopter while
looking through it.
★ The diopter range of the eyepiece is ±5
diopter. The number aligned to the line on the
viewing head is the diopter in use.
3.3.8 Adjusting the tension adjustment collar
(Fig.23)
Turn the tension adjustment collar①with your
fingers. When the collar is turned in the
direction of the arrow, tension of the coarse
adjustment knob②increases. Turning the
collar in the opposite direction decreases the
tension.
If the nosepiece descends on its own or if the
specimen gets out of focus quickly even when
it is brought into focus using the fine
adjustment knob③, it means the tension of
the coarse adjustment knob is too low. Turn the
collar in the direction of the arrow to increase
the tension
Fig.22
Fig.21
Fig.23

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4．Technical Specifications BS-2041B/T
1). Main Specifications
Optical System
Infinite optical system
Viewing Head
Siedentopf Binocular/Trinocular Head, 30°Inclined, Interpupillary Distance 48-75 mm
Eyepiece
Wide Field Eyepiece WF 10X/22mm
Nosepiece
Quadruple Nosepiece
Objective
Infinitive Plan Objectives 4×, 10×, 40×, 100×
Focusing
Coaxial Coarse and Fine Adjustment, Moving Range20mm, Fine Division 0.002mm
Condenser
Abbe Condenser, NA=1.25
Stage
Double Layers Mechanical Stage 140mm×140mm, Moving Range 75×50mm
Illumination
6V20W Halogen Lamp
2). Eyepiece and objectives
1. objective
Magnification
Numerical Aperture
Focal Length (mm)
Working Length (mm)
Objective
4×
0.10
45.3
17.3
dry
10×
0.25
17.96
10
dry
40×
0.65
4.5
0.54
dry
100×
1.25
1.81
0.13
oil
2. Eyepiece
Eyepiece
Magnification
Focal Length (mm)
Field of View (mm)
Wide field plan eyepiece
10×
25
Φ22

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5．Outfit BS-2041B/T
Main Body
Main Standard
〇
Double Layers Mechanical Stage
〇
Condenser Holder
〇
Viewing Head
Siedentopf Binocular Head
〇
Condenser
Abbe Condenser, NA=1.25
〇
Nosepiece
Quadruple
〇
Illumination
6V20W Halogen Lamp
〇
Spare Bulb
〇
Eyepiece
10×Wide Field Plan Eyepiece
〇
Objective
Infinite Semi-Plan Objective 4×
〇
Infinite Semi-Plan Objective 10×
〇
Infinite Semi-Plan Objective 40×
〇
Infinite Semi-Plan Objective 100×（Oil）
〇
Condenser
Bright Field Condenser with Adjustable Iris
Diaphragm
〇
Filter
Baby Blue, Green
〇

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6．Troubleshooting Guide BS-2041B/T
1. Optical System
TROUBLE
CAUSE
SOLUTION
1. The edge of the field
of view is dark or the
brightness is not
uniform
The nosepiece is not in the located
position (objective and light path not
coaxial)
Locate the nosepiece
properly where it clicks
The surface of the lamp becomes black
Change a new lamp bulb
A lens (the objective, condenser,
eyepiece or collector) is dirty.
Clean it thoroughly
2. Dirt or dust is visible
in the field of view
Dirt/dust on the specimen
Replace with a clean
specimen
Dirt/dust on the eyepieces
Clean them
3. Visibility is poor
Image is not sharp;
Contrast is poor;
Details are indistinct
Specimen is not covered
Add cover glass on it
The thickness of the cover glass is not
suitable
Use standard cover glass
with thickness of 0.17mm
Specimen is placed reversely
Turn it over
Dry objective has oil on it. (especially for
40X objectives)
Wipe the oil
A lens (the objective, condenser,
eyepiece or collector) is dirty.
Clean it
Immersion oil is not used with the 100x
objective
Use specified oil
Air bubbles existed in the immersion oil
Eliminate the bubble
The aperture iris diaphragm is stopped
down too far
Adjust the aperture iris
diaphragm properly
Dirt or dust on the eyepiece
Clean it
4. One side of image is
blurred
Condenser is not properly centered
Center the condenser with
the centering screw
The nosepiece is not properly engaged
Engage the nosepiece
properly
The specimen is not clamped
Clamp it with stage clips
5. The image is
yellowish
The blue filter is not used
Use the blue filter
6. The brightness is not
enough
The aperture iris diaphragm is too small
Adjust it properly
The condenser is too low
Adjust it properly
A lens (the objective, condenser,
eyepiece or collector) is dirty.
Clean it

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BS-2041B/T
2. Mechanical System
TROUBLE
CAUSE
SOLUTION
1. Field of view of
one eye does not
match that of the
other
Interpupillary distance is incorrect
Adjust interpupillary distance
2. Observation is
tiring
The diopter is not proper
Adjust the diopter properly
The brightness of the illumination is
not proper for eyes
Adjust the lamp voltage
3. Electrical System
TROUBLE
CAUSE
SOLUTION
1. The bulb cannot
light
No power supply
Check the power cord connection
The pin of the bulb doesn’t insert
properly
Insert the pin deeply
The bulb broken
Replace with a new one
2. The bulb burns out
suddenly
The bulb is not the specified one;
The voltage is too high
Use the specified bulb;
lower the voltage
3. the illumination is
not bright enough
the voltage is too low
Raise the voltage
4. Image flicks
The bulb is about to burn out
Replace with a new one
The bulb is not inserted deeply
Check its connection