The HF A is a computerized perimeter with a very comprehensive set of
test point patterns, strategies and custom tests. The instrument employs
several solutions which have proved useful in earlier computerized
perimeters and several new concepts. The construction with stimulus
generation through a projection system, input through a CRT, programmes
stored in PROMs and a double disc drive for storage of test results
makes it simple to adapt the instrument to future needs, whether these
are new test algorithms or point patterns, different input or display
screens or new statistical analysis programmes. All these changes could
be made without modification of actual instrument hardware.
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in glaucoma. A study of temporal and spatial summation. Arch.
Ophthalmol. 91: 463 -468 (1974). 2. Fankhauser, F. and Hiiberlin, H.
Dynamic range and stray light. An estimate of the falsifying effect of
stray light in perimetry. Documenta Ophthalmol. 50: 143-167 (1980). 3.
Fankhauser, F., Hiiberlin, H. and Jenni, A. Octopus programs SAPRO and
F. Two new principles for the analyses of the visual field. Graefes
Arch. Klin. exp Ophthal- mo1216: 155-165 (1981). 4. Gramer, E. and
Krieglstein, G.K. Zur Spezifitiit der iiberschwelligen Computer-
perimetrie. Klin. Mbl. Augenheilk. 181; 373-375 (1982). 5. Gramer, E.,
Kontic, D. and Krieglstein, G.K. Die computerperimetrische Dar- stellung
glaukomatoser Gesichtsfelddefekte in Abhangigkeit von der Stimulus-
grosse. Ophthalmologica 183: 162-167 (1981).