Microscope Anatomy Interactive Tutorials

• Simple Magnification

  Explore how a simple magnifying glass works with this tutorial designed to explain the concept of magnification. The visitor can use the mouse cursor to move a magnifying glass to change the image enlargement of an object.

• Transmitted Light Microscopy

  Explore the optical pathways in a typical transmitted light microscope. The visitor is able to control both the field and condenser iris diaphragms to vary the amount of light admitted into the microscope in this tutorial.

• Numerical Aperture Light Cones

  The featured tutorial was designed to illustrate how the angular aperture of a microscope objective is related to the refractive index of a medium and how the numerical aperture varies with the value of the angular aperture.

• Microscope Assembly

  Explore and learn how a microscope is assembled by using a mouse in this interactive java tutorial to "build" a complex microscope. All parts will snap into place when in the correct position.

• Microscope Stages

  Use this Flash tutorial to examine how a basic microscope mechanical stage operates. The stage illustrated below has two controls at the lower right that control translation in the X (side to side) and Y (front to back) directions.

• The Condenser Aperture Diaphragm

  Explore how incorrect use of the substage condenser aperture diaphragm can cause excessive glare and washing out of the sample as well as how closing it too much will result in increased diffraction.

• Condenser Light Cone Shapes

  Substage condensers produce unique light cones dependent partially upon the degree of optical correction. This tutorial explores the various light cones produced by condensers of increasing optical correction.

• The Field Diaphragm

  The aperture iris diaphragm in this tutorial controls how much light enters the microscope. Look as this tutorial allows the visitor to open and close the diaphragm and to see how this affects an image in the viewfield.

• Immersion Oil and Refractive Index

  The numerical aperture of an objective is partially dependent upon the refractive index of the imaging medium. This tutorial explores how changes in this value affect the light cone entering the objective.

• Objective Focal Length

  The focal length of an objective is dependent upon the magnification and the microscope tube length. This tutorial examines how changes in the tube length affect focal length in infinity-corrected microscopes.

• Centering the Lamp Filament

  Alignment of the microscope illuminator lamp filament is of fundamental importance in achieving Köhler illumination. This tutorial allows the student to experiment with the focus and alignment of the microscope lamp filament.

• Condenser and Field Diaphragm Alignment

  Correct adjustment of the condenser aperture diaphragm is very important aspects for obtaining superior image quality, because it controls the numerical aperture, resolving power, depth of field, and the overall image character.

• Lasers

  Examine and explore as this tutorial teaches how a ruby laser crystal works when excited by a xenon flash tube. Lasers are sometimes useful as light sources in optical microscopy.

Basic Microscope Ergonomics

• Microscope Observation Posture

  Learn about proper posture for microscope observations and demonstrates how new ergonomic microscope designs can lead to a reduction of associated musculoskeletal disorders in this interactive tutorial.

• Automatic Objective Changeover

  Examine the automatic objective changeover design in clinical microscopes, a feature that is quickly performed with a foot or hand switch to reduce the frequency of repetitive hand motion and ease operator discomfort.

• Ergonomic Eyepiece Observation Tubes

  Explore the range of currently available ergonomic observation tubes and their extended range of motion, which enables operators of all sizes and heights to comfortably view specimens for lengthy periods of time.

Microscope Optical Train

• Geometrical Construction of Ray Diagrams

  To represent a train of propagating light waves involves the application of geometrical optics determining size and location of images formed by a lens system. See how light rays can establish the parameters of an imaging scenario.

• Perfect Lens Characteristics

  The simplest imaging element in an optical microscope is a perfect lens, which ideally is free of aberration and focuses light onto a single point. Explore how light waves propagate through and are focused by a perfect lens.

• Perfect Two-Lens System Characteristics

  To represent a perfect lens as a system composed of two individual lens elements when a point source of light does not lie in the focal plane of a lens is common. Explore the off-axis oblique light rays passing through such a system.

• Viewing and Projection Eyepieces

  The eyepiece (or ocular) is designed to project either a real or virtual image. Explore how eyepieces can be coupled to the human eye or a camera system to produce images generated by the microscope objective.

• Condenser Image Planes

  Discover and explore the relationship between image planes relevant to the field and condenser diaphragms and how aperture size affects ray trace pathways in this interactive tutorial.

• Microscope Conjugate Field Planes

  Learn and explore the relationship between image planes relevant to the field and condenser diaphragms and how aperture size affects ray trace pathways in this interactive tutorial.

• Infinity Microscope Conjugate Field Planes

  Explore the relationship between image planes in a microscope with a tube lens for magnification of the intermediate image is determined by the ratio of the focal lengths of the tube and objective lens.

• Radius and Refractive Index Effects on Lens Action

  Analyze how variations in the refractive index and radius of a bi-convex lens affect the relationship between the object and the image produced by the lens.

• Olympus BX51 Microscope Light Pathways

  The featured interactive tutorial contains sliders and radio buttons that allow the user to adjust the intensity of illumination and to adjust a virtual beamsplitter that directs light to the eyepieces or a camera system.

• Tube Lens Focal Length

  Uncover the effect of tube lens focal length (short and long) on the angle of off-axis light rays in microscopes with infinity-corrected optical systems in this interactive java tutorial.

• Objective Magnification in Infinity Optical Systems

  Explore how changes in tube lens and objective focal length affect the magnification power of the objective in infinity-corrected microscopes.

Image Formation

• Airy Pattern Formation

  Explore and learn more about the origin of Airy diffraction patterns formed by the rear aperture of the microscope objective and observed at the intermediate image plane in this interactive tutorial.

• Airy Pattern Basics

  Explore how Airy pattern size changes with objective numerical aperture and the wavelength of illumination; it also simulates the close approach of two Airy patterns in this interactive java tutorial.

• Airy Disks, Numerical Aperture and Resolution

  Examine how Airy disk sizes vary with changes in objective numerical aperture (NA) and illumination wavelength and how these changes affect the resolution (R) of the objective in this interactive tutorial.

• Light Diffraction Through a Periodic Grating

  In this interactive tutorial, the visitor will be able to explore the mechanics of periodic diffraction gratings when utilized to interpret the Abbe theory of image formation in the optical microscope.

• Numerical Aperture and Image Resolution

  Examine the effects of objective numerical aperture on the resolution of the central bright disks present in the diffraction pattern, commonly known as Airy disks in this interactive tutorial.

• Conoscopic Images of Periodic Gratings

  The purpose of this tutorial is to explore the reciprocal relationship between line spacing in a periodic grid (simulating a specimen) and the separation of the conoscopic image at the objective aperture plane.

• Spatial Frequency and Image Resolution

  Discover the relationship between the distance separating these iris opening images and the periodic spacing (spatial frequency) of lines in the grating in this interactive java tutorial.

• Airy Patterns and the Rayleigh Criterion

  Examine how Airy disk sizes, at the limit of optical resolution, vary with changes in objective numerical aperture and illumination wavelength and how these changes affect the resolution of the objective in this tutorial.

• Axial Resolution and Depth of Field

  Explore the structure of cross sections taken along the optical axis of the microscope near the focal plane using a virtual high numerical aperture objective free from spherical aberration in this interactive tutorial.

• Periodic Diffraction Images

  The visitor will explore and examine diffraction images produced by a periodic object at several focal depths. The periodic object used in this interactive tutorial is a Siemens test star.

Optical Aberration

• Astigmatism Aberrations

  Explore the relationship between astigmatism and comatic aberrations, and how astigmatism aberrations are manifested by the off-axis image of a specimen point appearing as a line or ellipse instead of a point.

• Chromatic Aberration

  Learn more about chromatic aberrations and how when white light passes through a simple or complex lens system, the component wavelengths are refracted according to their frequency.

• Comatic Aberrations

  Learn about comatic aberrations and how they are mainly encountered with off-axis light fluxes and are most severe when the microscope is out of alignment, as well as the result of when these aberrations occur.

• Field Curvature Aberrations

  Learn and discover as this interactive tutorial explains the curvature of field in optical microscopy and how it is a common and annoying aberration that is familiar to most experienced microscopists.

• Geometric Distortion Aberrations

  Explore the two most prevalent types of distortion, positive and negative, and how they can often be present in very sharp images that are otherwise corrected for spherical, chromatic, comatic, and astigmatic aberrations.

• Spherical Aberrations

  Learn about the most serious of the monochromatic defects that occurs with microscope objectives, the spherical aberration, which causes the specimen image to appear hazy or blurred and slightly out of focus.

• Focus Depth and Spherical Aberration

  Explore an aberration-free meridional section of a point source of light located at a depth in the specimen layer having a refractive index and imaged with a virtual microscope objective in this tutorial.

• Coverslip Thickness Correction

  Examine as this tutorial demonstrates how internal lens elements in a high numerical aperture dry objective may be correctly adjusted with these varied cover glass thickness and dispersion fluctuations.