AmScope B490 Compound Binocular Microscope Instruction Manual

1. Product Overview

The AmScope B490 is a compound binocular microscope designed for biological and educational applications, offering high magnification and clear imaging. It features a sliding head for adjustable interpupillary distance, 10x widefield eyepieces, and a forward-facing nosepiece with four DIN achromatic objectives (4x, 10x, 40xS, 100xS oil). Illumination is provided by Brightfield halogen light with a rheostat for intensity control, paired with a 1.25 NA Abbe condenser and iris diaphragm. The microscope includes a double-layer mechanical stage with a stage stop and graduated coarse and fine focus with tension control.

Figure 1: AmScope B490 Compound Binocular Microscope, front-side view.

Included Components:

• AmScope B490 microscope with double-layer mechanical stage
• 10x widefield eyepieces (one pair)
• 4x DIN achromatic objective
• 10x DIN achromatic objective
• 40xS DIN achromatic objective
• 100xS (oil) DIN achromatic objective
• Immersion oil (one bottle)
• Color filters (blue and green)
• Spare halogen bulb
• Spare fuse
• Instruction manual

Figure 2: Included accessories: eyepieces, objectives, immersion oil, color filters, spare bulb, and fuse.

2. Setup Instructions

1. Unpacking: Carefully remove all components from the packaging. Retain the original packaging for future transport or storage.
2. Placement: Place the microscope on a stable, level surface away from direct sunlight, excessive heat, dust, and vibrations.
3. Head Assembly: Loosen the head retaining screw on the microscope body. Gently insert the binocular head into the top opening, ensuring it is fully seated. Tighten the retaining screw to secure the head.
4. Eyepiece Installation: Remove the protective caps from the eyepiece tubes and the eyepieces. Insert the two WF10x eyepieces into the binocular head's eyepiece tubes.
5. Objective Installation: Rotate the revolving nosepiece until the 4x objective is positioned over the stage opening. Install the remaining objectives (10x, 40xS, 100xS oil) clockwise into the nosepiece.
6. Power Connection: Ensure the power switch is in the 'OFF' position. Connect the power cord to the microscope's power input and then to a suitable electrical outlet (110V).

Figure 3: Side view of the microscope, showing focus knobs and power input location.

3. Operating Instructions

3.1 Power and Illumination

1. Turn on the main power switch located on the base of the microscope.
2. Adjust the illumination intensity using the rheostat knob on the side of the base. Start with a lower intensity and increase as needed for comfortable viewing.

3.2 Specimen Placement

1. Rotate the revolving nosepiece to select the lowest power objective (4x).
2. Raise the stage using the coarse focus knob to create enough space to place the specimen slide.
3. Open the stage clips on the mechanical stage and carefully place the specimen slide, securing it with the clips.
4. Use the X-Y stage control knobs to position the desired area of the specimen directly under the objective lens.

Figure 4: Front view of the microscope, highlighting the mechanical stage and objectives.

3.3 Focusing and Magnification

1. Interpupillary Distance: While looking through the eyepieces, adjust the sliding head to match your eye distance until a single, circular field of view is observed. The range is 55 to 75mm.
2. Dioptric Adjustment: If one eye is stronger than the other, use the diopter adjustment ring on one eyepiece to compensate, ensuring both eyes are in focus.
3. Coarse Focus: Slowly lower the stage using the coarse focus knob until the specimen comes into rough focus.
4. Fine Focus: Use the fine focus knob for precise focusing and to achieve a sharp image.
5. Changing Objectives: To increase magnification, rotate the revolving nosepiece clockwise to the next objective (e.g., from 4x to 10x). Due to the parfocal design, only minor fine focus adjustments should be needed.
6. Using 100xS Oil Immersion Objective: When using the 100xS objective, apply a small drop of immersion oil directly onto the specimen slide in the area to be viewed. Carefully lower the 100xS objective into the oil drop until it makes contact. Focus using the fine focus knob only. Always clean the 100xS objective and slide immediately after use to prevent oil from drying.

Figure 5: Close-up view of the objectives and mechanical stage.

3.4 Condenser and Iris Diaphragm Adjustment

1. The 1.25 NA Abbe condenser is mounted on a rack-and-pinion system, allowing its height to be adjusted. Raise or lower the condenser to optimize illumination for different objectives.
2. The iris diaphragm lever controls the aperture of the light beam. Adjust it to achieve optimal contrast and resolution for the specimen and objective in use. Generally, a smaller aperture increases contrast but reduces resolution, while a larger aperture increases resolution but reduces contrast.

4. Maintenance

4.1 Cleaning

• Optical Components: Use only specialized lens cleaning paper and lens cleaning solution. Gently wipe lenses in a circular motion. Avoid touching optical surfaces with bare hands.
• Body: Clean the microscope body with a soft, damp cloth. Avoid using harsh chemicals or solvents.
• Immersion Oil: After using the 100xS oil immersion objective, immediately clean the objective lens and the specimen slide with lens cleaning solution to prevent oil residue from hardening.

4.2 Bulb Replacement

If the halogen illumination fails, the bulb may need replacement. Ensure the microscope is unplugged and the bulb has cooled before attempting replacement. Refer to the diagram in the original packaging for specific bulb access. Use the provided spare halogen bulb (6V/20W).

4.3 Fuse Replacement

If the microscope does not power on, check the fuse. Ensure the microscope is unplugged. The fuse holder is typically located near the power input. Replace with the provided spare fuse of the correct rating.

4.4 Storage

When not in use, cover the microscope with a dust cover to protect it from dust and debris. Store in a cool, dry place. The anti-mold surfaces help preserve optics in high-humidity environments, but proper storage is still recommended.

5. Troubleshooting

6. Specifications

7. Warranty and Support

For warranty information, technical support, or service inquiries, please refer to the official AmScope website or contact AmScope customer service directly. Details regarding specific warranty periods and support procedures are typically provided with your purchase documentation or on the manufacturer's official channels.

Manufacturer: AmScope

Headquarters: Irvine, CA, USA