FIVS 215 Final Review: Exams 1&2

Antony Von Leeuwenhoek

Pioneer of microscopy; created simple microscopes.

Robert Hooke

First to use the term 'cell' in microscopy.

Hans and Zacharias Janssen

Credited with the invention of the microscope.

Carl Zeiss

Microscope design innovator; principles still used today.

Köhler Illumination

Technique for achieving uniform illumination in microscopy.

Anatomical Orientation

Terms describing positions in relation to the body.

Superior

Direction towards the head in anatomical terms.

Inferior

Direction away from the head in anatomical terms.

Medial

Position along the midline of the body.

Lateral

Position away from the midline of the body.

Anterior (ventral)

Refers to the front side of the body.

Posterior (dorsal)

Refers to the back side of the body.

Proximal

Closer to the point of attachment on the body.

Distal

Further from the point of attachment on the body.

Real Image

Formed by light rays intersecting; seen through objective.

Virtual Image

Appears to converge; formed by eyepiece lens.

Lens Formula

f = focal length, p = object distance, q = image distance.

Magnification

Ratio of image distance to object distance (m = q/p).

Back Focal Plane

Located behind the objective, where primary image forms.

Conjugate Focal Planes

Light paths connecting specimen to eyepiece and retina.

Least Distance of Vision

Minimum distance for clear vision; 10 inches/25 cm.

Stereo Microscope

Provides three-dimensional viewing of specimens.

Angular Aperture

Maximum angle of light rays captured by objective lens.

Infinity-optics

Path with parallel rays between objective and tube lens.

Color Temperature

Describes warmth or coolness of light colors.

Eyepoint

Position for optimal viewing through the eyepiece.

Snell's Law

Describes relationship between incidence and refraction angles.

Angle of Incidence

Angle light strikes a surface; equals angle of reflection.

Diffuse Reflectance

Light reflected off a surface at many angles.

Specular Reflectance

Light reflected in a single direction off a surface.

Index of Refraction (RI)

Ratio of light speed in vacuum to light speed in medium.

Strong Relief

Substance's RI significantly differs from mounting medium's RI.

Low Relief

Substance's RI closely matches mounting medium's RI.

Critical Angle

Minimum angle for total internal reflection to occur.

Dispersion

RI changes with wavelength; shorter wavelengths have higher RI.

Dispersion Curves

Graphs estimating material stiffness and wave velocity.

Becke Line

Lines indicating RI differences between substance and oil.

Numerical Aperture (NA)

Measure of lens's ability to gather light.

Airy's Disk

Diffraction pattern from parallel light through an aperture.

Abbe's Rule of Thumb

Minimum magnification is 500x NA; maximum is 1000x NA.

Empty Magnification

Magnification beyond useful range, no additional detail.

Diffraction Formula

n = d Sin(θ); relates diffraction to wavelength.

Resolution Limit

Minimum resolvable distance; calculated using 0.61λ/NA.

Calibrated Ocular Micrometer

Tool for measuring specimen size using micrometer divisions.

Lord Rayleigh's Criteria

Two patterns distinguishable when central maximum overlaps minimum.

Immersion Methods

Techniques for measuring RI using Becke lines and shadows.

GRIM

Device using monochromatic light to measure glass RI.

Abbe's Diffraction Theory

Diffraction patterns act as light sources for imaging.

Spherical Aberration

Variation in focal length causes fuzzy images.

Chromatic Aberration

Different wavelengths focus at different points.

Curvature of Field

Image distortion due to lens curvature; corrected by apertures.

Distortion

Image magnification changes with distance from center.

Astigmatism

Different focal distances for perpendicular planes.

Kohler Illumination

Technique for optimal illumination in microscopy.

Condenser Function

Concentrates light onto specimen for better imaging.

Ocular Micrometer Calibration

Use full scale for accurate measurement comparisons.

Fiber Thickness Measurement

Determines fiber identity and characteristics.

Trilobal fibers

Measured from outer edge to low point.

Dominant eye

Identified by focusing and closing each eye.

Becke line

Moves towards higher refractive index when focused.

Refractive index parameters

Affected by wavelength and temperature.

GRIM3

Instrument for automatic refractive index measurements.

Cargille

Major manufacturer of refractive index oils.

Crystal systems

Classification of crystals based on symmetry.

Isotropic

Cubic crystals with uniform light behavior.

Uniaxial Anisotropic

Includes tetragonal, hexagonal, rhombohedral structures.

Biaxial Anisotropic

Includes orthorhombic, monoclinic, triclinic structures.

Pleochroism

Color change with orientation to polarized light.

Retardation

Calculated as birefringence x thickness x 1000.

Birefringence

Difference between two principal refractive indices.

Isotropism

Uniform light behavior in all directions.

Anisotropism

Different light behavior depending on orientation.

Double refraction

Two light paths in birefringent materials.

Calcite Rhomb

Doubly refractive crystal splitting light into two rays.

Starch Grains ID

Identified by cross-shaped extinction in polarized light.

Extinction types

Parallel, oblique, and symmetrical based on angles.

Isotropic Indicatrix

3D plot of refractive index versus direction.

Uniaxial Indicatrix

Has one optic axis and two principal refractive indices.

Biaxial Indicatrix

Has two optic axes and three principal refractive indices.

Color temperature

Describes warmth or coolness of light sources.

Omega ray

Vibrates tangentially to isochrones.

Epsilon ray

Vibrates radially in quadrants.

Optic Sign

Determined by the difference between e and w.

Optic Angle

Measured as 2V, 2H, and 2E.

Tobi's method

Calculates optic parameters using d/D ratio.

Spindle Stage

One-axis rotation device for optical measurements.

EXCALIBR

Software for calculating optical extinction data.

Monochromatic Interference Filter

Transmits narrow wavelength range via destructive interference.

Phase Contrast Microscopy

Technique enhancing interference conditions for microscopy.

Annulus Ring

Separates direct rays from diffracted rays in PCM.

Hoffman Modulation Contrast

Uses slit aperture for oblique light entry.

Bright Field Microscopy

Produces dark images on bright backgrounds.

Dark Field Microscopy

Uses oblique light for dark backgrounds.

Dispersion Staining

Technique using stops to identify samples' colors.

Central-Stop D.S.

Blocks light in the center for color identification.

Annual Stop D.S.

Creates a small circle of light for staining.

Wayne Williams Case

Forensic case highlighting fiber evidence in murder.

Vegetable Fibers

Includes cotton and kapok, used individually.

Animal Fibers

Includes wool, silk, and domestic animal hair.

Mineral Fibers

Asbestos, a type of mineral fiber.