Microscopy, in essence, refers to the different techniques of coming up with structural images that can be visible by the naked eye, with the aid of a magnification device such as a microscope. Today, there are three known fields of microscopy, one of which is optical microscopy.

Optical microscopy makes use of visible light that passes through a sample with the use of one or more than one lenses. This permits for a clearer and vivid view of the specimen. The image can be seen by the naked eye by capturing it digitally, as with the aid of a digital biological microscope, or through photographic plate.

Dark Field Microscopy

Dark field microscopy is a kind of illumination technique common in optical microscopy. It is used to create contrast in samples that are not stained. The principle behind dark field microscopy is this: the sample is illuminated by the light which isn’t collected by the microscope’s objective lens. Therefore, it doesn’t form a portion of the specimen. The resulting image is that of a dark image with bright light surrounding it.

Where Is It Used?

The principle of dark field microscopy is very much applied to experiments and studies involving biological samples that are live as well as not stained. They are very simple yet truly effective. These samples include singe-cell organisms from water as well as a tissue culture’s smear. Because the setup is simple, the kinds of images you get out of the techniques are actually excellent. The only problem with the dark field microscopy is that you need to transmit strong light, which can only add damage to your samples.

You can use a simple dissecting microscope when you are utilizing the dark field microscopy. If you want to set it up, you should place the specimen on top of the opening. This way, the light will only reflect on the surfaces covered by the slide and the cover slip. It will not reflect on the surface located underneath the slide. You may also have to use a stand, which is capable of holding the slide. All built-in illuminators should also be turned off. Then reflect light at its very high intensity into the specimen.

Bright Field Microscopy

The technique known as bright field microscopy makes use of an incandescent light, which is directed towards your lens which is located underneath the stage. This is referred to as condenser. The light, which passes through the lens, will then be aimed at the specimen and then to the person’s eyes with the aid of an eyepiece or ocular, which is basically the second magnifying lens.

Light that passes through the stains or natural pigmentation are absorbed which makes them very visible in the light path. It doesn’t matter that they are colorless. For example, a bacterium such as paramecium will become highly visible if you use a bright field microscope, though you may not be able to catch its organelles or cilia.

Normally, a good microscope, such as a digital biological microscope, is equipped with an illuminator that is built in to the system. It also contains an adjustable condenser, binocular eyepiece, as well as a mechanical stage.

Advantages and Limitations of a Bright Field Microscopy

Bright field microscopy is recognized because it’s very easy to set it up. All you need are the basic equipment, including a biological microscope. There is no need to prepare any kind of sample; thus, you can simply view and monitor live cells. However, with its advantages, it also has its own limitations. For one, it has very low optical resolution. It could be attributed to the material that is out of focus. It also produces the lowest contrast when it comes to numerous biological samples.

You can further enhance it if you can adjust the source of light though the microscope’s iris diaphragm. You may also make use of objective lens that suits oil immersion. You can use immersion oil over the glass cover. It can tremendously improve the image’s resolution as well as refracts light. You can also utilize different kinds of simple and differential stains.

Dark Field Microscopy and the Biological Microscope

The objective lens in the dark field microscopy is similar to those used in the bright field. However, the more advanced ones contain special kind of condenser. The condenser of advanced biological microscopes can illuminate a specimen with the use of light’s annulus ring. Thus, the object appears a lot darker except for areas of the specimen which scatter light back into the microscope’s objective lens.

You need more ideas on field microscopy, you can read information at digitalbiologicalmicroscopes.com.