Question

Can you tell me about the microscope parts and purpose of the laminar flow cabinet. Pleasee explain it in detail. Thank you in advance, I appreciate it!!

Answer 1

Parts of a Microscope.

A microscope on a whole has three portions, On the top it starts with eye piece lens and tube followed by the arm usually curved to hold and lift a microscope and onto which a microscope specimen stage is fixed and finally the base.

There are two sets of lenses, one for the eyepiece through which we look through and the other is the objective lens which relays the image of the magnified specimen or object and is closer to it. The eyepiece lens is ocular and has settings of the range 10x to 30x , but the ones which are used in regular activities are 10x and 15x.

The eyepiece tube connects the eyepiece lens to the objective lens positioned above the specimen platform or stage.

The arm as mentioned before acts like a back bone. The base is ofcourse for support and stability and the light source or illuminator is attached at the base in such a way thhat thhe light passes through the hole in specimen stage and reaches the objective lens and finally to the ocular lens.In some microscopes the illuminator source is a reflected light on a mirror attached to the base in place of the light.

The stage or platform is the place where the slides are placed, held in place by clips on either side with spring action. And they have a knob at the side to move the slide sideways inorder to facilitate specimen positioning under the objective lens.

Turret is the next piece which holds the set of objective lens of different magnifications and can be rotated according to the magnification required, say if 40X is required the particular objective lens can be brought to the center by revolving the turret.

Objevctive lens is a part of the magnification device in addition to the eyepiece's magnification. This usally has four objective lenses with magnifications of 4x, 10x, 40x and 100x, of which the 100x is usually used for oil imersion observation of samples for more resolution.

The rack stop is a movement limiting part and prevents the objective getting to close to the slide.,

The econdenser lens and diaphragm placed under the stage helps to focus the light onto the specimen. Condenser lenses are required for very high power.

Laminar air flow cabinet

A laminar flow cabinet is an enclosed workbench which is used to create an aseptic environment to prevent contamination of the samples worked upon and also to keep the environment safe for the worker.

The main feature of laminar flow hood is the presence of HEPA filters (high efficiency particulate absorbing) which filters the air outside the cabinet while entering the inside of the cabinet in a one way smooth vertical and downward laminar air flow. the air then leaves the cabinet through the space between the glass screen and the steel platform through the worker slides the hands in to work in the cabinet.

The laminar flow cabinets have an ordinary light source and a UV source to use for decontamination or for sterilisation of the platform before and after use.

These cabinets are of two tyopes one is horizontal flow cabinets and the other is vertical flow cabinets, of which the vertical flow cabinets are the most preffered because of its compact size comparitively and because of the safe flow direction which is otherwise in horizontal cabinets the worker is more disposed to the microbial contaminated air coming out from the hood.