by Rajan Gupta | Aug 25, 2020 | Optical Instruments
A microscope is an optical instrument which is used to see highly magnified images of tiny objects such as bacteria, cells , viruses and protozoans etc. because these tiny objects cannot be seen by naked eyes. In this chapter we shall study two types of microscopes:...
by Rajan Gupta | Aug 25, 2020 | Optical Instruments
Cataract Cataract is usually found in old persons. Cataract causes the loss of eye sight due to the formation of an opaque membrane over the eye lens. Correction of Cataract This defect cannot be corrected by using any type of spectacles. The only method...
by Rajan Gupta | Aug 25, 2020 | Optical Instruments
Due to Hypermetropia the eyes are able to see the distant objects clearly but cannot see the nearby objects clearly. In this case the image of nearby object is formed beyond the retina. Cause of Hypermetropia An eye suffers from Hypermetropia due to the following two...
by Rajan Gupta | Aug 25, 2020 | Optical Instruments
Due to myopia the eyes are able to see nearby objects clearly but cannot see the distant objects clearly. This defect is caused due to the formation of image of distant object in front of the retina. Cause of Myopia An eye suffers from the defect of myopia...
by Rajan Gupta | Aug 25, 2020 | Optical Instruments
Human eye is very sensitive organ of the body. It is essential for every individual to take full care for keeping human eye healthy. There are many types of defects that develop in human eye. Following are the common defects found in a human eye: Myopia or...
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