Condenser microscope function

The polarized light microscope is designed to observe and photograph specimens that are visible primarily due to their optically anisotropic character. In order to accomplish this task, the microscope must be equipped with both a polarizer, positioned in the light path somewhere before the specimen, and an analyzer (a second polarizer), placed in the optical pathway between the objective rear aperture and the observation tubes or camera port. Image contrast arises from the interaction of plane-polarized light with a birefringent (or doubly-refracting) specimen to produce two individual wave components that are each polarized in mutually perpendicular planes. The velocities of these components are different and vary with the propagation direction through the specimen. After exiting the specimen, the light components become out of phase with each other, but are recombined with constructive and destructive interference when they pass through the analyzer. When an anisotropic specimen is brought into focus and rotated through 360 degrees on a circular polarized light microscope stage, it will sequentially appear bright and dark (extinct), depending upon the rotation position. When the specimen long axis is oriented at a 45-degree angle to the polarizer axis, the maximum degree of brightness will be achieved, and the greatest degree of extinction will be observed when the two axes coincide. During rotation over a range of 360 degrees, specimen visibility will oscillate between ...

All microscopes are designed to include a stage where the specimen (usually mounted onto a glass slide) is placed for observation. Stages are often equipped with a mechanical device that holds the specimen slide in place and can smoothly translate the slide back and forth as well as from side to side. A stage can be classified according to design and functionality. In the simplest case, the plain stage (illustrated in Figure 2, on the left) consists of a rectangular or square design containing several clips to hold the specimen slide. The stage illustrated in Figure 1 is a typical rectangular stage with the added feature of a specimen slide translational control device commonly referred to as a mechanical stage. This mechanical stage contains controls for right-handed microscopists that allow the movement of the specimen slide in both the X (right and left) and Y (back and forth) directions so the microscopist can examine the entire microscope slide (secured to the stage with the slide holder). Similar mechanical stages are available with the translational control knobs situated on the left-hand side of the stage for left-handed microscopists. The stage illustrated in Figure 1 also contains a rather large opening in the center to allow light from the condenser to pass through the specimen (the stage opening). The stage is also equipped with a locking control that allows the stage to be fixed into position with respect to its rotation around the condenser axis. Graduated lo...

Table of Contents • • • • • • What is condenser microscope? A microscope condenser, also called a substage condenser when it’s not above the stage (as in an inverted microscope), is defined as an optical lens which renders a divergent beam from a point source into a parallel or converging beam to illuminate an object. What is the condenser on a light microscope used for MCQ? The condenser lens is placed between the light source and the specimen and it gathers and focuses the light rays in the plane of the microscopic field to view the specimen. What are the functions of condenser and iris diaphragm? The condenser concentrates and controls the light that passes through the specimen prior to entering the objective. It has two controls, one which moves the Abbe condenser closer to or further from the stage, and another, the iris diaphragm, which controls the diameter of the beam of light. How do the functions of a condenser and an iris diaphragm differ? The iris diaphragm regulates how much light is on the object being viewed, and the condenser focuses light into an objective as it moves up and down enhancing specimen contrast. What is the function of stereo microscope? A stereo microscope is used for low-magnification applications, allowing high-quality, 3D observation of subjects that are normally visible to the naked eye. In life science stereo microscope applications, this could involve the observation of insects or plant life. What is the main function of a condenser? Th...