Lens in a microscopefunction

A red filter blocks green light and blue light: Only red light can get through to your eyes. The white banana and the yellow peel both reflect some red light, so the whole banana looks red (see below; click to enlarge):

The objective (lens closest to the specimen) focuses on the specimen outside the focal point creating a real image.  This image from the objective actually increases the detail or resolving power of that specimen.  Resolution of the microscope is what allows the human eye to see detail they cannot see with the naked eye.  It allows the viewer to enter the microworld.  The higher the objective lens the better the resolution.  The eyepiece does not contribute anything new to the image; it simply spreads out the details.  This is referred to as empty magnification. This is why eyepieces are always less than 20 times magnification.

Objectivelens microscopefunction

Likewise, a pure blue filter transmits only blue light, and a pure green filter transmits only green light. Any color from a picture that is not transmitted by the filter will be absorbed by the filter and will not be seen.

Place one colored filter at a time over a colored picture and notice how the colors are affected. With a red filter, the picture appears entirely in shades of red plus black.

Print your name or a short message on a piece of white paper using a different color of crayon, pencil, or pen for each letter. Then look at the message through a red filter. You may notice that the red letters disappear, but you can still see blue or green letters. By figuring out which colors you still see and which you don’t, you can write a secret message and then use the filter as the decoder.

Lens in a microscopediagram

Here, a magenta filter blocks green light and a cyan filter blocks red light (see below; click to enlarge). Only blue light can pass through to your eyes. The banana looks blue because the white fruit reflects some blue light. But the yellow peel looks black. It reflects no blue light.

Whichlensis usedin microscopeconvex or concave

Different types of lenses in the microscope can cause rays to travel in different directions depending on the angle of the incident or source rays.  Light rays going through the lens can cause the light to converge or diverge, depending on whether the lens is concave or convex.  Biconvex (converging) lenses are thickest at the center and biconcave (diverging) are thinnest at the center.  There are many varieties of lenses that can be utilized with an optic system.

A yellow filter blocks blue light, so only red light and green light can get to your eyes. The white banana and the yellow peel both reflect some green light and some red light. The whole banana looks yellow because green light plus red light mix to make yellow light (see below; click to enlarge):

Most colors of light can be made by mixing three primary colors of light: red light, blue light, and green light. Most colors of pigments, however, can be made by mixing magenta, cyan, and yellow pigments. Magenta pigment reflects red and blue light. More important, it absorbs, or subtracts, green light. Cyan pigment subtracts red light. Yellow pigment subtracts blue light. Four-color printing in magazines is done with inks of these three colors—magenta, cyan, and yellow—plus black. Mixed properly, these pigments produce the entire range of colors found in colored pictures in magazines.

Magazine illustrations are colored with pigments, but when you look at the illustration, you are sensing the light that is being reflected to your eyes.

What is objectivelens in microscope

Types oflens in a microscope

An ideal red filter transmits only red light and absorbs all other colors. In this ideal case, a picture containing red, green, and blue would appear red and black when viewed through a red filter.

The focal length or focal distance is the distance between the center of a converging thin lens and the point at which parallel rays of incident light converge; or the distance between the center of a diverging lens and the point from which parallel rays of light appear to diverge. The point at which it intersects the focal plane is called the "focal point." The distance from the lens to the image is called the "optical element-image distance."

A brightly colored picture takes on a whole new look when you view it through a colored filter, which transmits some colors and absorbs others. Using a colored filter, you can even decode secret messages written with colored pens or crayons.

When you view multicolored writing through an ideal red filter, only red light reaches your eyes. Red light comes from both the red letters and the white paper (since white contains all colors). The red letters tend to disappear because they blend right in with the red light from the white paper. Letters that contain no red would appear black. Because most pigments are not perfectly pure, you may notice that more than just the red letters blend in with the background. That is, if a yellow letter reflects red (since yellow light can be made from a combination of red light and green light), the yellow letter would blend in with the background.

Light going through a double convex (biconvex) lens will converge at a focal point.  If a biconvex lens is near an object inside its focal point, a virtual upright image can be seen.   The lenses of the microscope’s eyepiece (closest to your eye) create a virtual image because your eye is within the focal point.  The eyepiece will only enlarge the image of the specimen.