Parts of the Microscope and Their Uses
- The Eyepiece Lens. •••
- The Eyepiece Tube. •••
- The Microscope Arm. •••
- The Microscope Base. •••
- The Microscope Illuminator. •••
- Stage and Stage Clips. •••
- The Microscope Nosepiece. •••
- The Objective Lenses. •••
The compound microscope has two systems of lenses for greater magnification, 1) the ocular, or eyepiece lens that one looks into and 2) the objective lens, or the lens closest to the object.
The microscope body tube separates the objective and the eyepiece and assures continuous alignment of the optics.
Compound light microscopes
A microscope is an instrument that is used to magnify small objects. Some microscopes can even be used to observe an object at the cellular level, allowing scientists to see the shape of a cell, its nucleus, mitochondria, and other organelles.
In a modern microscope it consists of a light source, such as an electric lamp or a light-emitting diode, and a lens system forming the condenser. The condenser is placed below the stage and concentrates the light, providing bright, uniform illumination in the region of the object under observation.
In naval terms, turret traditionally and specifically refers to a gun mounting where the entire mass rotates as one, and has a trunk that projects below the deck. The rotating part of a turret seen above deck is the gunhouse, which protects the mechanism and crew, and is where the guns are loaded.
A trading turret is a specialised phone system used by people who work in the financial industry. It's designed for traders who experience a high volume of calls and need access to multiple lines to carry out split-second deals.
A turret punch or turret press is a type of punch press used for metal forming by punching. Punching, and press work in general, is a process well suited to mass production. However the initial tooling costs, of both the machine and the job-specific press tool, are high.
The turret is an armored structure supporting one or more guns -- typically a heavy cannon and a couple of machine guns. Turning the traverse gear rotates the turret on the hull, allowing the tank crew to aim the main gun without turning the entire tank. The crew can also pivot the main gun up and down.
To avoid eye strain, you'll want to take frequent microbreaks to rest your eyes (momentarily close the eyes or focus on far away objects to vary focal length). Spread microscope work throughout the day or rotate the work among several colleagues. Move the microscope to the edge of the counter to avoid a tilted neck.
Turrets were weapon mounts designed to protect the crew and mechanism of the artillery piece and with the capability of being aimed and fired in many directions as a rotating weapon platform.
nountower; part of tower. bell tower. campanile. carillon. clocher.
A turret holds a group of tools and rotates to bring a new cutting tool into position. Changing tools involves: Pulling the current tool back, typically with a Z-axis or combined X- and Z-axis motion. Rotating the turret until the correct tool is in position.
Terms in this set (13)
- body. Separates the lens in the eyepiece from the object lenses below.
- Nose piece. Holds the object lenses above the stage and rotates so that all lenses may be used.
- eyepiece. Magnifies the thing by 10.
- high power lens. Biggest lens and magnifies 40 times.
- Stage.
- diaphragm.
- Mirror or light.
- Arm.
The objective lens of a microscope is the one at the bottom near the sample. At its simplest, it is a very high-powered magnifying glass, with very short focal length. This is brought very close to the specimen being examined so that the light from the specimen comes to a focus inside the microscope tube.
The 4X lens is called the scanning or low power lens. It has the widest field of view, allowing you to look at large parts of the specimen, and the greatest depth of field.
There are two major types of eyepieces that are grouped according to lens and diaphragm arrangement: the negative eyepieces with an internal diaphragm and positive eyepieces that have a diaphragm below the lenses of the eyepiece.
Low Power Objective (LPO) has a magnifying power of 10x which means that the specimen is 10x magnified when it is viewed under the microscope. Meanwhile, HPO (High Power Objective) has a magnification of 40x which means that, the specimen viewed under the microscope is magnified 40x.
The principal limitation of the light microscope is its resolving power. Using an objective of NA 1.4, and green light of wavelength 500 nm, the resolution limit is ∼0.2 μm. This value may be approximately halved, with some inconvenience, using ultraviolet radiation of shorter wavelengths.
scanning-power objective lens
At 100x magnification you will be able to see 2mm. At 400x magnification you will be able to see 0.45mm, or 450 microns. At 1000x magnification you will be able to see 0.180mm, or 180 microns.
For example, optical (light) microscopes are usually equipped with four objectives: 4x and 10x are low power objectives; 40x and 100õ are powerful ones. The total magnification (received with 10x eyepiece) of less than 400x characterizes the microscope as a low-powered model; more than 400x as a powerful one.
These parts include:
- Eyepiece – also known as the ocular.
- Eyepiece tube – it's the eyepiece holder.
- Objective lenses – These are the major lenses used for specimen visualization.
- Nose piece – also known as the revolving turret.
- The Adjustment knobs – These are knobs that are used to focus the microscope.
The objective lens consists of several lenses to magnify an object and project a larger image. According to the difference of the focal distance, lenses of different magnifications are available, such as 4x, 10x, 40x, and 50x.
Wet-mount Slides A wet-mount slide is when the sample is placed on the slide with a drop of water and covered with a coverslip, which holds it in place through surface tension. Advantages – This type of slide preparation allows you to view microscopic living things without them drying out.
The microscope diaphragm, also known as the iris diaphragm, controls the amount and shape of the light that travels through the condenser lens and eventually passes through the specimen by expanding and contracting the diaphragm blades that resemble the iris of an eye.
FOCUS ON SPECIMEN, FIRST USING THE COARSE AND THEN THE FINE FOCUS CONTROLS. YOU MAY HAVE TO MOVE THE SLIDE AROUND ON THE STAGE OF THE MICROSCOPE TO BRING THE SPECIMEN INTO THE VIEWING AREA.
FINE ADJUSTMENT KNOB — A slow but precise control used to fine focus the image when viewing at the higher magnifications.
Among the choices above, in viewing the bacteria we should use an objective lens that has a magnification of 600 or higher. Thus, the answer is letter A. 60x objectives with immersion oil and 10x eyepiece. Bacteria are very minute organism so we have to use a higher magnification.
