Magnifying
glass is of great use in many types of laboratories. In a biology laboratory
students use the magnifying glasses to take a closer look at plant and
animal specimens. Things like a strand of hair, leaf structures etc. can be
observed with great detail using magnifying lenses. A magnifying glass is a
lens looking through which make things appear of bigger size as a result
intricate details of the objects can be observed.
A magnifying glass typically consist of a convex lens that is bound by a
metallic or plastic frame with a handle for hand held magnifying glasses.
This convex lens is made using plastic or glass. By putting the magnifying
lens at the right distance between the object and the eyes a person can read
small words, perform intricate jewellery work and lot many other things
apart from use in biology laboratories.
Some important
definitions concerning Magnifying Lenses
- Focal Length or Working Distance : Higher the power of a
lens, shorter would be the working distance. Besides power, a
magnifying lens can be classified by a working distance.
- Magnifying Power : Magnifying power is the capacity of
the lens to increase an object's visual size. This factor is denoted
by X(times)
- Field of View : Field of view denotes the size of the
area which is seen through the magnifying glass.
- Depth of Field : Depth of field is actually the distance
which a magnifier is moved above an object while still keeping the
object in focus. Higher the magnification, shorter is the depth of
field.
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Choosing a Magnifying Lens
A magnifying glass though looks like a simple instrument but purchasing it
can be a tricky affair. It has been often found that the buyer has bought a
wrong type of magnifying glass which is not suited to his needs. To avoid
this type of problems it is essential to understand the needs before
procuring one from the dealer. The following point may prove to be useful.
- What are the items to be magnified? : By asking this question
the size and dimension of the magnifier can be understood. A basic rule
regarding the size of magnifier is that smaller the diameter of
magnifying glass, more closer is the eye need to be brought in before
the object to get a correct focus. For getting a higher magnification
small magnifying glasses are more suited
- Details of the items to be observed : This is next most
important question while selecting a magnifying glass. Details of the
things to be observed helps in ascertaining the necessary magnification.
- Where the magnifier is intended for use : This question
should help to decide about a magnifying glass's shape and if any
accessories are needed. For outdoors activities a folding magnifier
along with a cover is quite justified. makes a lot of sense. If the the
magnifier is used in dim light conditions, then it is better to use the
one that has an in-built lighting system. Still for students who need to
keep both their hands free a magnifier on an adjustable stand will
suffice.
- Economical factors concerning magnifying glass : It has been
seen that other things being equal higher the price for a specific
magnification better is the quality of the glass.
- Other factors : Other factors like if spare parts are easily
obtainable, if the magnifying glass gives the true image are also no
less important while selecting magnifying glass.
Types of Magnifying
Glasses
Plastic Magnifying Lenses
The plastic magnifying glass is great for young scientists at work! Use the
plastic magnifying lenses for getting a close look at insect specimen in
your courtyard or look how a sliced orange looks like. The rugged and
durable magnifying lenses are quite suitable for individual research or for
science experiments in laboratories or classrooms that do not require
microscopes. Recent developments in the plastic moulding processes have made
plastic lenses quite popular. As compared to glass a plastic magnifying
glass offers quite a handful of advantages that includes:
- Plastic magnifying glasses are cheaper
- Lightweight
- Less in fragility
Lamp
Magnifier
A lamp magnifier can be clamped onto any surface for observing small
objects very clearly and closely. The incandescent lamp magnifier uses a
standard bulb for intense brightness, while the magnifying window helps to
bring small objects into full view. Use the lamp magnifiers for a hands-free
viewing.
Magnifying
Glass with Stand
magnifying glass with stand helps to see the papers and other documents
while making a presentation. The sturdy base of the stand ensures you can
keep your hands free and position the glass exactly where you need it. The
glasses can be removed any time for using it as routine magnifying glass.
Pocket Magnifier
A pocket magnifier is perfect for a number of applications. While no one
can doubt its efficacy in reading small and fine prints, in a garden it is
the next best tool available to entomologist other than gloves. A hand lens
or pocket magnifier gives the convenience of carrying them anywhere without
any hassle. So go out identify the small insects, mites around your garden
and appreciate the immense value of the hand lens. A 10x magnification of
the hand lens suffices for getting a close up view of the potential pests.
Using a pocket magnifier or hand lens is very easy. Postion your eyes close
to the lens and then by moving your head focus correctly on the sample by
adjusting it with hand. By regular practice using the pocket magnifier can
be very easy.
