Biomedical Engineering Reference
In-Depth Information
Fig. 6.16 The width of the
axial response (full width at
half-maximum intensity), for
dry, water and oil immersion
objectives
is shown in Fig. 6.16 , for dry, water and oil immersion objectives. For a given
numerical aperture, the dry objective results in the best resolution, as then the
angular aperture is greatest.
6.6
Conclusions
A confocal microscope is often built around a commercial conventional microscope
by adding a scan head with facility to scan the beam, a laser source, a detector
and appropriate filters. Alternatively, the system can be constructed from optical
components and laid out on an optical table. Close-coupled galvo mirrors with
position feedback control are usually adequate. For fast scanning, some method of
multiplexing (by illuminating with arrays of points or a line) is desirable to avoid
saturation of fluorophores, but some degradation of imaging performance cannot be
avoided. The confocal pinhole should be kept at a small size to optimize signal-to-
noise ratio. A water immersion objective of high numerical aperture is usually the
best option for biological applications.
References
1. M. Minsky, Microscopy apparatus. 3,013,467 Filed 7 Nov 1957 - Issued 19 Dec 1961
2. H. Goldman, Spaltlampenphotographie und -photometrie. Ophthalmologica 98 , 257-270
(1940)
3. Z. Koana, J. Illum. Eng. Instit. 371 , 26 (1943)
4. H. Naora, Microspectrophotometry and cytochemical analysis of nucleic acids. Science 114 ,
279-280 (1951)
5. M.D. Davidovits, M.D. Egger, Scanning laser microscope. Nature 223 , 831 (1969)
6. A.F. Slomba, D.F. Wasserman, G.I. Gaufman, J.F. Nester, A laser flying spot scanner for use in
automatised fluorescence antibody instrumentation. J. Assoc. Adv. Med. Instrum. 6 , 230-234
(1972)
7. M. Petran, M. Hadravsky, M.D. Egger, R. Galambos, Tandem scanning reflected light
microscope. J. Opt. Soc. Am. 58 , 661-664 (1968)
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