Zoology- Animal Physiology and techniques in Biology
Types of microscopes
Microscopes are designated as either light microscopes or electron
microscopes. The former use visible light or ultraviolet rays to illuminate
specimens. They include brightfield, darkfield, phase-contrast, and
fluorescent instruments. Fluorescent micro-scopes use ultraviolet radiations
whose wavelengths are shorter than those of visible light and are not directly
perceptible to the human eye. Electron microscopes use electron beams
instead of light rays, and magnets instead of lenses to observe sub
microscopic particles.
Light microscope
A light microscope is a biology laboratory instrument or tool, that uses visible
light to detect and magnify very small objects, and enlarging them.
They use lenses to focus light on the specimen, magnifying it thus producing
an image. The specimen is normally placed close to the microscopic lens.
Microscopic magnification varies greatly depending on the types and number
of lenses that make up the microscope. Depending on the number of lenses,
there are two types of microscopes i. e Simple light microscope (it has low
magnification because it uses a single lens) and the Compound light
microscope (it has a higher magnification compared to the simple microscope
because it uses at least two sets of lenses, an objective lens, and an eyepiece).
The lenses are aligned in that, they can be able to bend light for efficient
magnification of the image.
The functioning of the light microscope is based on its ability to focus a beam
of light through a specimen, which is very small and transparent, to produce
an image. The image is then passed through one or two lenses for
magnification for viewing. The transparency of the specimen allows easy and
quick penetration of light. Specimens can vary from bacterial to cells and
other microbial particles.
Types of light microscopes
, Zoology- Animal Physiology and techniques in Biology
With advancement in science, the microscopes used to view specimens are
both simple and compound light microscopes, all using lenses. The difference
is simple light microscopes use a single lens for magnification while
compound lenses use two or more lenses for magnifications. This means, that
a series of lenses are placed in an order such that, one lens magnifies the
image further than the initial lens. The modern types of Light Microscopes
include:
➢ Bright field Light Microscope
➢ Phase Contrast Light Microscope
➢ Dark-Field Light Microscope
➢ Fluorescence Light Microscope
Let us learn about Phase contrast and fluorescent microscopes as mentioned
in the syllabus.
Phase Contrast Microscope
This is a type of optical microscope whereby small light deviations know as
phase shifts occur during light penetration into the unstained specimen.
These phase shifts are converted into the image to mean, when light passes
through the opaque specimen, the phase shifts brighten the specimen forming
an illuminated (bright) image in the background.
Types of microscopes
Microscopes are designated as either light microscopes or electron
microscopes. The former use visible light or ultraviolet rays to illuminate
specimens. They include brightfield, darkfield, phase-contrast, and
fluorescent instruments. Fluorescent micro-scopes use ultraviolet radiations
whose wavelengths are shorter than those of visible light and are not directly
perceptible to the human eye. Electron microscopes use electron beams
instead of light rays, and magnets instead of lenses to observe sub
microscopic particles.
Light microscope
A light microscope is a biology laboratory instrument or tool, that uses visible
light to detect and magnify very small objects, and enlarging them.
They use lenses to focus light on the specimen, magnifying it thus producing
an image. The specimen is normally placed close to the microscopic lens.
Microscopic magnification varies greatly depending on the types and number
of lenses that make up the microscope. Depending on the number of lenses,
there are two types of microscopes i. e Simple light microscope (it has low
magnification because it uses a single lens) and the Compound light
microscope (it has a higher magnification compared to the simple microscope
because it uses at least two sets of lenses, an objective lens, and an eyepiece).
The lenses are aligned in that, they can be able to bend light for efficient
magnification of the image.
The functioning of the light microscope is based on its ability to focus a beam
of light through a specimen, which is very small and transparent, to produce
an image. The image is then passed through one or two lenses for
magnification for viewing. The transparency of the specimen allows easy and
quick penetration of light. Specimens can vary from bacterial to cells and
other microbial particles.
Types of light microscopes
, Zoology- Animal Physiology and techniques in Biology
With advancement in science, the microscopes used to view specimens are
both simple and compound light microscopes, all using lenses. The difference
is simple light microscopes use a single lens for magnification while
compound lenses use two or more lenses for magnifications. This means, that
a series of lenses are placed in an order such that, one lens magnifies the
image further than the initial lens. The modern types of Light Microscopes
include:
➢ Bright field Light Microscope
➢ Phase Contrast Light Microscope
➢ Dark-Field Light Microscope
➢ Fluorescence Light Microscope
Let us learn about Phase contrast and fluorescent microscopes as mentioned
in the syllabus.
Phase Contrast Microscope
This is a type of optical microscope whereby small light deviations know as
phase shifts occur during light penetration into the unstained specimen.
These phase shifts are converted into the image to mean, when light passes
through the opaque specimen, the phase shifts brighten the specimen forming
an illuminated (bright) image in the background.
