Why do we use lens combination in optical instruments?

Why do we use lens combination in optical instruments?

Combination of lenses is used in various optical instruments because: (i) To increase the magnification of the image. (ii) To increase the sharpness of the image. (iv) To minimise certain defects or aberrations in the image formed by a single lens.

What is a lens in an optical instrument called?

Thus a telescope consists of a long focal length lens called the object glass and a short focal length lens called the eyepiece, and the magnification is equal to the ratio of the focal lengths.

Why combination of lenses are used in optical devices like telescope and microscope?

A compound microscope uses multiple lenses to create an enlarged image that is easier for a human eye to see; this is due to the fact that the final image is farther away from the observer, and therefore the eye is more relaxed when viewing the image.

Which optical instrument shows arrangement of lenses?

a) Arrangement of lenses shown in the figure is refracting telescope.

What is the use of combination of lenses?

Combination of lenses. When two lenses are used in combination, the first one forms an image that then serves as the object for the second lens. The magnification of the combination is the ratio of the height of the final image to the height of the object.

What are the advantages of combination of lens?

The use of a combination of lenses increases the sharpness of the image.

What are three common types of optical instruments?

Three optical instruments are cameras, microscopes and telescopes.

Cameras are optical devices which focus light on a piece of film to record and allow user to record an image of an object, either on photo paper or digitally.

What is the simplest optical instrument?

A simple microscope is an optical instrument, we use for the magnification of small objects to get a clear image or vision. It is a convex lens having a short focal length. This microscope is at a small distance from the object for the magnification and hence this forms a virtual image.

What is the basic purpose of optical instruments?

An optical instrument (or “optic” for short) is a device that processes light waves (or photons), either to enhance an image for viewing or to analyze and determine their characteristic properties. Common examples include periscopes, microscopes, telescopes, and cameras.

What is the importance of lenses in the microscope?

While the modern microscope has many parts, the most important pieces are its lenses. It is through the microscope’s lenses that the image of an object can be magnified and observed in detail.

What are 5 optical instruments?

Spectrometer or monochromator for generating or measuring a portion of the optical spectrum, for the purpose of chemical or material analysis. Autocollimator which is used to measure angular deflections. Vertometer which is used to determine refractive power of lenses such as glasses, contact lenses and magnifier lens.

What happens when you put a concave and convex lens together?

Hint: When a concave lens and a convex lens of the same focal length are in contact, then the power of the lens combination will be zero and its focal length will be infinite. Therefore, the combination behaves as a plane glass plate.

What are the lenses at the viewing end of optical instruments?

Combination of lenses at the viewing end of optical instruments • Concerned with pupils? • Visionary?

Which is part of the microscope holds two objective lenses?

Holds the slide in place on the stage Stage Clips Supports upper part of the micrpscope Arm Connects the eyepiece to the objective lenses Tube Holds two or more objective lenses and can be rotated to change power Nosepiece Combination of lenses at the viewing end of optical instruments Eyepiece

When to use a combination of thin lenses?

Combination of Thin Lenses The image of an object can be made erect and much magnified by using more than one lenses. Therefore suitable combination of lenses are used in high powered optical instruments. the above expression is for the combination of two lenses where f1 is the focal length of one lens and f2 is the focal length of the other.

What is the equation for pairs of lenses in contact?

The equation (5) shows that for a pair of lenses in contact the sum of the reciprocals of their individual focal lengths is equal to the reciprocal of the focal length of the combination.