Bertrand lens An accessory lens which may be inserted into the light path above the analyser in a transmitted-light microscope. When determining vibration directions or interference figures using parallel or convergent polarized light, the Bertrand lens is inserted to bring the image of the interference figures into focus. Alternatively, if the Bertrand lens is absent, the eyepiece may be removed and the vibration directions or interference figures observed by looking down the microscope tube. The lens was first used in 1878 by E. Bertrand who adapted an original (1844) design by G. B. Amici. In petrological Refractive Microscopes its applicability is more to determine the Mineral type by identifying the interference figures. it shows whether the mineral is Uniaxial or Biaxial and also +ve or _ve.
To produce a magnified image of an object that is subject to your scrutiny.
The purpose of the arm is so that when you put your eye to the lens, that it doesn't move, and it holds the lens still so the image is not blurry.
You could insert a second lens in the focal path, between the object and the first lens. The second lens can be designed (or moved) to focus the image on the screen. This is the same function that eyeglasses do for people with poor vision. The second lens, the eyeglasses, are inserted between the viewed object and the lens of the eyes. The second lens is designed to correct the distortion of the eye lens, thus creating an in-focus object on the "screens" of the eyes.
concave lens are shape in wardsconvex bends light rays to meet at focus
A simple microscope has two lenses. One the eye looks through and the objective lens nearest the object being observed. Changing the objective lens changes the magnification of the microscope, and can also change the amount of light on the object. The objective lens draws the light rays together to make a sharp image.
Is small optical element mounted just below the ocular.
Objective lens function is to show the microcosm in 3 different zooms.
The function of lens is to to form an image of an object by converging or diverging rays of light from the object.
An eyepiece lens takes the bright light from the focus of the objectivce lens and magnifies it :)
Eyepiece Lens or Ocular Lens is the lens on top. This is use to see the things or objects to observe or to study.
To view the object
It makes the light diverge.
used to focus the image
It makes an image to fall on the retina. For this function the thickness of the lens is changed according to the distance of the object.
Eye piece and . . .lens ;-)
The eye lens is kept in place by ciliary muscles. These muscles can contract or relax.If the ciliary muscles contract or relax the focal length of the eye lens becomes large or small.Or in other words the function of the eye lens is to increase or decrease the focal length of the eye lens.
Bertrand Lavier has written: 'Bertrand Lavier'