DE1722472U - PERIMETER FOR QUALITATIVE AND QUANTITATIVE PERIMETRY. - Google Patents

Description

The innovation relates to a device with which one can see the field of vision of the human eye can determine "

There are already devices that can be used to determine the field of view can »Msn distinguishes between two basic types: b« * i will be the one type a test hair moved over a pivotable spherical meridian. Here the luminance of the test mark is not infinitely variable and the luminance of the surroundings cannot be regulated at all. The second kind the previous devices for determining the field of view, one speaks of so-called perimeters, uses a half hollow sphere in which the check mark can be moved in all meridians Jcann. The luminance the test mark and that of the environment could be more or less precisely controlled and regulated.

The * first basic type has the decisive disadvantage that the luminance of the test mark and the in-field lighting cannot be regulated in such a way that they can always be kept constant regardless of all external influences. Due to this deficiency, the fields of view were by no means to be regarded as exact measurements. Both basic types, however, have the disadvantage that only qualitative perimetry is possible with them, i.e. a test mark of constant luminance is fed from the outside at the intersection of all meridians until the person to be examined notices the test mark when looking at the intersection of all meridians. A quantitative perimetry is therefore not possible with the aid of the devices described. With quantitative perimetry in its one embodiment, the other does not differ fundamentally from it, the person to be examined looks at the intersection of all meridians. The test mark is now placed at any point on a meridian and the luminance is increased until the threshold value is reached at this point in the field of vision, that is, until the person to be examined notices the test mark. The sensitivity of the associated retinal site is measured in ** £ ·.

The purpose of the innovation is to remedy the deficiencies mentioned. In order to remedy the deficiency described above, the perimeter was the first-mentioned reason type a © control and regulation possibility for the

Luminance of the test mark and the surrounding lighting attached. from an innovation: in the second basic type, abstinence was taken for the reason, since the manufacturing costs for this type are high and

"£ &, May 32. 1722472. Dr. mcd. Christa Epphardt née Lubinus and Eilhard Koppenhöfcr, Eutin (Holst). | Perimeter for qualitative and quantitative Pcrimctric. March 17, 56. E SI97. (T- 4; Z. 1)

17th

Since tests have shown that it is even more in the sense of exact perimetry if the luminance can be kept largely constant than that the entire environment is illuminated evenly, which of course would be achieved to a greater extent by a hollow sphere. In order to achieve a sufficiently precise, temporal constant of the luminance, a photocell a in connection with an ammeter I was used. Cell a is attached to the lower edge of the Meridian Kia. The mirror Sp is tilted until it clicks into place, causing the test mark to fall on the photocell a. In the circuit of the lamp of the projector P there is a regulator R ₁ , with which the luminance of the test mark can be regulated to a certain pointer deflection of the instrument I. The luminance of the surroundings can be regulated with the same camera and the same measuring device by the controller R to a certain pointer deflection of the instrument I, which is in the circuit of the two lamps L ₄ and L ^. A surface silver-plated version is used for the mirror, since the reflection losses on it remain constant even at large angles of incidence. As a result of the innovations mentioned, the examination conditions are kept largely constant, which greatly enhances the accuracy of the measurements. In order to remedy the second deficiency, i.e. also to create the possibility for quantitative perimetry, a regulator R, was also placed in the circuit of the test mark lamp, on the scale of which the sensitivity of the relevant parts of the skin can be read in t * Ur .

Automatic recording of the values for both types of perimetry was omitted in order not to drive up the production price too high. Instead, the values read on the scale at R ₃ are carried on a scale on the runner _{piece I 1} aD, l ^ can be moved to 1, JLn in a direction of movement that is perpendicular to that of 1. The whole runner is over the form shiftable, which already contains the standard sensitivities expressed in line lengths (plotted vertically upwards) in the relevant Gesinhtsfeidpunkte. With the scale at I ^ the measured value is plotted on the straight line that represents the hormonal sensitivity, as a result of which a pressure pin is pressed _{at the upper end of the scale of I 1.} To make the fittings easier to handle, all buttons and the instrument have been moved to a control panel. In order to avoid switching all the individual switches % n / a collective switch B was used, the five positions of which allow the operating modes "C

42b, 32 05.! 722 472. Dr. "CD. ChrtitJ Epp'hard't gcb. Lubinus and Eilhard Koppenhöfcr. Eutin (Hoist.). | Perimeter for Qualitative and Quantitative Pcrinsctnc. 17.3.56. E S! 97. (T- 4; Z!)

To facilitate quantitative perimetry in particular the horiaontele scale of the test mark snaps into place every 5 ° mn for the qualitative fex- imetriii be repealed. Pie vertical

Scale snaps into place every 15 ° · Around the luminance differences in the surrounding area as low as possible; üu hold became a sideways sitxeu of the examiner Paid, because movements in particular falsify the measurement results TJm keep the light beacon differences in the surrounding area to a minimum »

the device must be set up in front of a wall that is the same color like the ganae device; However, it should reflect more light as it does

from L. and L. is farther away than the meridian Kxu

1 *

Claims (5)

Epphardt née Lubinus and Eilhard Kop-1 '(. Penhöfcr. Eutin (Holst.). | Perimeter for qualitative and quantitative perimctric. 3/17/56 . ■ * 1.) Device characterized aur determination of the field of view, that for the luminance of the test mark of a swiveling ball— Meridians a bridgeable, stepless Hegel possibility is provided is, 2 ·) Device according to claim 1, characterized in that a photo- electrical device is built in 3.) Device according to claim 1 and 2, characterized in that one each non-bypassable, stepless regulator for the luminance of the test mark and the surrounding lighting is provided 4.) Device according to claim 1 to 3, characterized in that all Switch and controller are combined in one control panel. 5.) Device according to claim 1 to 4, characterized in that a two-part runner is located in front of the control panel.