Introduction to Leica professional polarising microscopes and what to look for
Application of Polarising Microscope: Polarising microscope is a kind of microscope used to study the so-called transparent and opaque anisotropic materials and to observe the substances with birefringence. Basic principle of polarizing microscope: A polarizing microscope must have the following accessories: polarizing lens, detecting lens, compensator or phase piece, special stress-free objective lens, rotating stage.
Characteristics of Polarising Microscope: The method of changing ordinary light into polarised light for microscopic examination to identify whether a substance is monorefractive (isotropic) or birefractive (anisotropic). Birefringence is a fundamental property of crystals. Therefore, polarising microscopes are widely used in the fields of minerals and chemistry, as well as in biology, botany and liquid crystal research.
Ways of polarising microscopy:
(1) Positive phase microscopy: also known as aberration-free microscopy, which is characterised by the use of low-magnification objective lenses, without the use of Bertrand lenses (BertrandLens), the object of study can be studied directly with polarised light. At the same time, in order to make the illumination aperture smaller, push away the upper lens of the condenser. Positive phase mirror inspection is used to check the birefringence of the object.
(2) Cone light microscopy (Conoscope): also known as interference microscopy, the study of the interference pattern produced during the interference of polarised light, this method is used to observe the uniaxial or biaxial nature of the object. In this method, a strongly converging polarised beam of light is used for illumination.
Requirements of polarising microscope in terms of device:
(1) Light source: monochromatic light is preferred because the speed, refractive index, and interference phenomena of light vary due to the wavelength. Ordinary light can be used for general microscopy. 2) Eyepieces: eyepieces with crosshairs are to be used. 3) Bertrand lens: an auxiliary component in the optical path of the condenser lens, this is an auxiliary lens that magnifies all the primary phases caused by the object into secondary phases. It ensures that the eyepiece is used to observe the interference pattern formed in the focal plane behind the objective lens.
Leica microscope use precautions: to ensure the service life and reliability of the system, pay attention to the following matters:
(1) The test room should have three preventive conditions: shockproof (away from the source of vibration), moisture-proof (using air conditioning, dryer), dust-proof (the ground on the floor); power supply: 220V +-10%,50HZ temperature: 0 degrees -40 degrees.
(2) When focusing, pay attention not to make the objective lens touch the specimen, so as not to scratch the objective lens.
(3) When the carrier table gasket hole centre position near the centre of the objective lens, do not switch the objective lens, so as not to scratch the objective lens.
(4) Brightness adjustment should not be too big or too small, and do not over-bright, affecting the service life of the bulb, but also detrimental to the eyesight.
(5) all (function) switching, the action should be light, in place.
6) Turn off the power to minimise the brightness.
