The in‐line transmission of polycrystalline high‐density ceramics is discussed in terms of light scattering by pores. The Mie theory for light scattering is applied to calculate scattering coefficients using generalized parameters. Results are shown for scattering by spherical pores with uniform size and with a lognormal size distribution. Specific examples are given of the calculated transmission of alumina in the wavelength region 0.4–5 μm. Experimentally determined transmission curves of normally sintered and of hot‐pressed alumina are compared with calculated curves. The porosity, the position of the maximum, and the width of the lognormal distribution are treated as variables in the calculation. Good agreement with the experimental data is obtained.

1.
R. L.
Coble
,
J. Appl. Phys.
32
,
793
(
1961
).
2.
G.
Winkler
,
IEEE Trans. Magn.
MAG‐7
,
773
(
1971
).
3.
J. G. J.
Peelen
,
Sci. Ceram.
6
,
XVII
(
1973
).
4.
D. W.
Lee
and
W. D.
Kingery
,
J. Am. Ceram. Soc.
43
,
594
(
1960
).
5.
N.
Grimm
,
G. E.
Scott
, and
J. D.
Sibold
,
Ceram. Bull.
50
,
962
(
1971
).
6.
D. W.
Budworth
,
Spec. Ceram.
5
,
185
(
1970
).
7.
G. J.
Oudemans
,
Proc. Brit. Ceram. Soc.
12
,
83
(
1969
).
8.
Rubis Synthétique des Alpes, Extra Pure A6.
9.
Union Chimique Belge, pro analysi.
10.
H. C. van de Hulst, Light Scattering by Small Particles (Wiley, New York, 1957).
11.
M. Kerker, The Scattering of Light and Other Electromagnetic Radiation (Academic, New York, 1969).
12.
J. V.
Dave
,
IBM J. Res. Dev.
13
,
302
(
1969
).
13.
I. H.
Malitson
,
J. Opt. Soc. Am.
52
,
1377
(
1962
).
14.
G.
Tomandl
,
Ber. Dtsch. Keram. Ges.
48
,
222
(
1971
).
15.
H. J.
Oel
,
Ber. Dtsch. Keram. Ges.
43
,
624
(
1966
).
16.
R.
Metselaar
,
P. J.
Rijnierse
, and
U.
Enz
,
Ber. Dtsch. Keram. Ges.
47
,
663
(
1970
).
17.
R. O.
Grumprecht
and
C. M.
Sliepcevich
,
J. Phys. Chem.
57
,
90
(
1953
). According to these authors the scattering cross section Csca has to be corrected with a factor F = 1−iθ2/Qx2. Here i is the intensity function of the scattered wave, which can be calculated from the Mie theory (Ref. 10). We find that F increases with the size parameter x. In our experiments the highest value of x is about 20 and this gives 1−F = 5×10−3. This means a correction of 0.5% upon Csca.
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