20 STEREOPHOTOGRAMMETRIE IN DER MIKROSKOPIE, HUBENY
Literatur
[1] Hubeny, K., Beiträge zur Nah- und Mikrobildmessung, Photographische Korres-
pondenz, 85. Band, Nr. 7/8, Seite 51-57, 1949.
[2] Hubeny, K., Probleme und Leistungsfähigkeit der Nah- und Mikrobildmessung,
Photographische Korrespondenz, 91. Band, Nr. 10, Seite 161-164, 1955.
[3] Hubeny, K., Photogrammetrische Aufnahmen mit geteilter Eintrittspupille,
Photogrammetria, 1942, Seite 117-121.
[4] Hubeny, K., Einige nicht-topographische Anwendungen der Photogrammetrie
und deren Problematik, Österreichische Zeitschrift für Vermessungswesen, Son-
derheft 19, Seite 115 ff.
[5] Gotthardt, E., Zur räumlichen Ausmessung von Objekten mit dem Elektronen-
mikroskop, Z. Phys., S. 714-717, 1942.
[6] Helmeke, J. G., Theorie und Praxis der elektronenmikroskopischen Stereoauf-
nahmen. Teil I bis III, Optik, 11, S. 201-225, 1954 u.f.
[7] Burkhardt, R., Der Elmigraph I, ein neues Gerät zur räumlichen Ausmessung
und Kartierung von elektronenmikroskopischen Bildpaaren. Teil 4, Optik, 12, S.
417-429, 1955.
[8] Hubeny, K. Über die Ausmessung von elektronenmikroskopischen Stereobild-
paaren, Photographische Korrespondenz, 95. Band, Nr. 5, Seite 72-77, 1959.
u.a.
SUMMARY.
It is possible to produce space-images which can be measured stereoscopically, not
only with the photo-microscope, but also with the electronic microscope. For an arbitrary
enlargement n there is a characteristic value resulting from a difference in depth dy,
which has been added to a parallax difference, which is just recognizable (the absolute
resolving power in the direction of the axis) as well as the range T within which the
image is sufficiently sharp. This range depends not only on the enlargement and the
dy
aperture of the bundles of rays, but also on the wave-length; the ratio v is the relative
resolving power which tallies with the range within which the image is sufficiently
sharp in the direction of the optical axis. This relative resolving power, which may be
represented as a linear function of the wave-length, is the decisive criterion with regard
to the applicability of the measurement of the image in space in microscopy.
When approaching the value unity for this ratio, an observation in space is no longer
possible; for measuring purposes it is necessary to limit the value to a maximum in the
range 0.01— 0.02. As a result the enlargements in the photo-microscope become restricted;
on the other hand the electronic microscope permits nearly all enlargements for meas-
uring purposes as a consequence of the short wave-lengths.
The arrangement for taking photomicroscopic stereo-photographs should be the same
as that for a normal case in terrestrial photogrammetry; restitution can easily be car-
ried out with the aid of approximation formulae relating to this restitution. A descrip-
tion is given of a plotting instrument developed by the author, as well as an example
of application (intersection lines with an interval of 0.01 mm).
The conditions for an electronic microscope are absolutely different. Not considering
the very favourable value of the resolving power mentioned above, which allows the
production of spatial images even with great enlargements, the procedure of representa-
tion corresponds approximately to a parallel projection; consequently the only possible
way of taking photographs is that of convergence.
The orientation of each single stereophoto in its own plane, generally only known by
approximation, the angle of convergence also only known approximately, as well as pos-
