Microscope Parts and Functions | How to Use a Microscope

Summary

In this practical class by Manoj Academy, the instructor explains the parts and functions of a compound light microscope. Viewers learn how the microscope uses a light source to illuminate specimens, and the significance of the two lenses (eyepiece and objective) in magnifying images. Key components like the arm, stage, coarse and fine adjustment screws, and diaphragm are detailed. The class also demonstrates how to properly focus on a prepared slide, using an example of Spirogyra algae, achieving magnifications of up to 2500x. The session concludes by inviting viewers to explore more courses online.

Takeaways

• 🔬 The class covers the basic components and functionality of a compound light microscope.
• 💡 It's called a light microscope because it uses light, such as LED or natural light, to illuminate specimens.
• 👓 A compound microscope uses two lenses with different magnifications to provide a much larger final image.
• 🦶 The base of the microscope is called the 'foot,' while the 'arm' holds the body of the microscope.
• 🔍 The eyepiece lens has different magnifications, such as 25x, and the objective lenses have varying magnifications (e.g., 10x, 45x, 100x).
• 📏 The microscope stage holds the specimen in place with clips and allows light to pass through for observation.
• 🔦 LED light or a plano-concave mirror is used to focus light on the specimen, with the diaphragm controlling light intensity.
• 🛠 The coarse adjustment screw moves the body and lenses for rough focusing, while the fine adjustment screw provides more precise control.
• 🧪 Glass slides hold the specimens, often covered with a cover slip to protect them during observation.
• 🔬 The microscope provides a total magnification by combining the eyepiece and objective lens powers, reaching up to 2500x magnification in this demonstration.

Q & A

Why is it called a light microscope?

It is called a light microscope because it uses a source of light, such as an LED bulb or natural/artificial light, to illuminate the specimen being observed.

What makes the microscope a 'compound' microscope?

It is known as a compound microscope because it uses two sets of lenses—an eyepiece lens and objective lenses—to achieve higher magnification of the specimen.

What is the function of the eyepiece lens in a compound microscope?

The eyepiece lens is used to further magnify the image created by the objective lens. It typically has magnifications like 10x, 15x, or 25x.

What is the purpose of the objective lenses in the microscope?

The objective lenses, which are attached to the rotatable nosepiece, provide different levels of magnification (e.g., 10x, 45x, 100x) to zoom in on the specimen. The user can switch between them for various magnifications.

What role does the diaphragm play in the microscope?

The diaphragm adjusts the amount of light entering the microscope, similar to how the iris in a human eye controls the size of the pupil. This helps in controlling the brightness of the field.

How do the coarse adjustment and fine adjustment screws function?

The coarse adjustment screw moves the microscope's body up and down to bring the specimen into focus. The fine adjustment screw allows for more precise focusing without moving the body noticeably.

What is the purpose of the slide and coverslip in microscopy?

A slide holds the specimen in place on the stage, and the coverslip protects the specimen from damage, drying out, or contamination while observing it under the microscope.

What is the function of the mirror in older microscopes?

In some microscopes, a plano-concave mirror is used to collect and focus light from different directions onto the specimen. The concave side focuses the light onto the specimen more effectively.

How does magnification work in a compound microscope?

Magnification in a compound microscope is a product of the objective lens magnification and the eyepiece lens magnification. For example, if using a 100x objective lens and a 25x eyepiece lens, the total magnification would be 2500x.

How do you move a slide to adjust the view of the specimen?

Certain microscopes have screws that allow you to move the slide left, right, forward, or backward for fine adjustments. If these screws are not present, you must manually adjust the slide.