Microscopy: History, Types, Parts, and Parameters

Vocabulary flashcards covering the history of microscopy, types of microscopes, microscope components, and parameters of imaging.

Hans and Zacharias Janssen

Dutch spectacle makers credited with creating the first compound microscope in 1590.

Galileo Galilei

Italian scientist who invented a compound microscope using convex and concave lenses in 1609.

Giovanni Faber

Scientist who coined the word "microscope" in 1625 by analogy with telescope.

Robert Hooke

Known as the "English Father of Microscopy," he published Micrographia in 1665, introducing detailed drawings of microscopic structures and coining the term cell.

Antonie van Leeuwenhoek

Dutch scientist who launched microbiology in 1676 using handcrafted single-lens microscopes with $270\times$ magnification to observe bacteria, protozoa, and sperm cells.

Titan Krios

A modern microscope invented in 2018 that represents a pinnacle of microscopy, allowing researchers to visualize biological molecules at an atomic level.

Dissecting Microscope

Also known as a stereomicroscope, a microscope designed for low-magnification observation of a sample using light reflected from the surface of an object rather than transmitted through it.

Compound Microscope

The most common microscope type used in schools and laboratories, which uses visible light and a series of glass lenses to magnify thin, transparent specimens at ranges typically from $40\times$ to $1,000\times$.

Transmission Electron Microscope (TEM)

A type of electron microscope where electrons pass through an ultra-thin specimen to view internal cell structures at magnifications up to $1,000,000\times$.

Scanning Electron Microscope (SEM)

A type of electron microscope in which electrons scan the surface of a specimen coated in gold or carbon to produce detailed 3D images of surface topography.

Scanning Probe Microscope (SPM)

A class of microscopes that form images by physical interaction, using a very sharp tip to "feel" a surface as it scans back and forth to achieve atomic resolution.

Scanning Tunneling Microscope (STM)

A specific type of Scanning Probe Microscope that uses an electrical tunneling current jumping between a sharp conducting tip and a conductive surface to image and manipulate individual atoms.

Body Tube

A hollow cylinder that maintains the proper distance between the eyepiece and the objective lenses.

Draw Tube

A smaller tube located at the upper end of the body tube that holds the ocular lens.

Revolving Nosepiece

A rotating disk at the bottom of the body tube that holds the objective lenses, allowing the user to switch between magnifications.

Arm

The curved handle used for carrying the microscope and supporting the body tube.

Stage

The flat platform where the slide is placed, containing a central hole called the stage aperture to allow light to pass through.

Coarse Adjustment Knob

The larger knob used to move the stage or body tube up and down significantly to bring the specimen into general focus.

Fine Adjustment Knob

The smaller knob used for sharp, detailed focusing after general focus has been established.

Stage Clips

Metal clips attached to the stage that hold the slide firmly in place.

Base

The V-shaped or U-shaped bottom part that supports the entire microscope.

Pillar

The vertical extension from the base that connects to the arm.

Inclination Joint

A joint that allows the microscope to be tilted back for more comfortable viewing.

Condenser

A lens system located beneath the stage that concentrates and directs light onto the specimen.

Iris Diaphragm

A component located under the condenser that regulates the amount of light and controls image contrast.

Ocular Lens (Eyepiece)

The magnifying lens located at the top of the microscope that you look through, typically providing $10\times$ magnification.

Scanning Objective

The lowest-power objective lens ($4\times$ magnification) used for initial viewing of a specimen.

Low Power Objective (LPO)

An objective lens providing $10\times$ magnification, used to view the general structure of a specimen.

High Power Objective (HPO)

An objective lens providing $40\times$ or $60\times$ magnification, used for observing fine details of a specimen.

Oil Immersion Objective (OIO)

An objective lens providing maximum magnification ($100\times$), requiring a drop of synthetic or cedar oil on the slide.

Resolution

The ability of a lens system to distinguish two close points as separate entities, determining the amount of fine detail visible.

Contrast

The difference in intensity or color between the specimen and the background, essential for making transparent biological specimens visible.

Magnification

The process of enlarging the apparent size of an object, expressed as a ratio between the image size and the actual specimen size.

Total Magnification

The overall magnification calculated in a compound microscope using the equation $\text{Total Magnification} = \text{Power of Ocular Lens} \times \text{Power of Objective Lens}$.