Special metallurgical microscope objective lens classification
Metallographic microscope special objective classification special objective lens is designed and manufactured specifically to achieve some specific observation effect, there are mainly the following kinds:
1, with correction ring objective (Correctioncollarobjective): in the middle of the objective lens is equipped with a ring mounted adjusting ring, when turning the adjusting ring, can be adjusted within the objective lens lens between the distance between the lens group, so as to correct by the coverslip thickness is not standard coverage caused by the difference. Adjustment ring on the scale can be from 0.11-.023, in the objective lens shell is also marked with this number, indicating that the coverglass can be corrected from 0.11-0.23mm thickness between the error.
2, with iridescent diaphragm objective (Irisdiaphragmobjective): in the upper part of the objective lens barrel equipped with iridescent diaphragm, the outer side can also be rotated adjustable ring, rotating the size of the aperture of the diaphragm can be adjusted, this structure of the objective lens is ** oil immersion objective, it is the role of the dark field of view when the microscopic examination, the background of the field of view is not dark enough, resulting in the reduction of microscopic examination of the quality. This time to adjust the size of the diaphragm
3, phase contrast objective (Phasecontrastobjective): this objective is used for phase contrast microscopy special objective, which is characterised by the focal plane of the objective lens is equipped with a phase plate.
4, no cover objective (Nocoverobjective): some of the objects being examined, the top can not be added with a coverslip, so that in the microscopic examination should be used without a cover objective, otherwise the image quality will be significantly reduced, especially in the high-magnification microscopy is more obvious. This objective lens is often engraved on the shell NC, at the same time in the position of the thickness of the coverslip without the word 0.17, but engraved with "0".
5, long working distance objective: the focal length of this objective is greater than the ordinary objective, it is designed to meet the liquid material (high temperature metallography), liquid crystal, tissue culture, suspension and other materials designed for microscopy.
