Device for measuring orientation of maxwell center of mass, in particular in people suffering from chanting difficulty

Abstract

The invention solves the deficiencies of the prior art by proposing an electronic device which can measure the key orientation of an ellipse, and in particular the corresponding orientation of the main axes of both eyes which can lead to a reading disorder of a child, with an accuracy of 2 DEG. The device according to the invention comprises a unit for testing the orientation of the elliptical profile in order to be able to measure a mirror image or translation orientation that may lead to a reading disorder. In fact, the opposite or parallel orientation of two contours of the same ovality may particularly result in two types of reading difficulties. Observation of each Maxwell centroid and its oriented intraocular image through an aiming system with a rotating blue-green dual filter makes it possible to diagnose various types of reading difficulties. Advantageously, the rotation system makes it possible to select the frequency of rotation in order to optimize the quality of contrast.

Description

Technical Field

[0001] The invention relates to a device which makes it possible, in particular for persons suffering from dyslexia, to measure all possible orientations between Maxwell centroid contours (including ellipse contours) about two foveas, applicable to all possible orientations of the main axes of the ellipse. Background Art

[0002] Dyslexia is generally defined as a complex learning deficit that specifically affects reading and that manifests in childhood. Although various pathways based on biology, neurology, cognitive science and genetics have been proposed, they all converge on biological origins related to neurology and brain connectivity. The deficit is highly prevalent, affecting approximately 10% of the population according to international statistics, with all countries affected to the same degree.

[0003] Vision originates from both eyes and provides the brain with two largest information flows, of which subtle differences in the visual cortex have been suspected to be involved since the beginning of the 20th century. Visual confusion and confusion of symmetrical letters such as "b" and "d", and even confusion of words and their mirror images, prompted Ernest Mach (The analysis of sensations, Chicago: Open Court 1914) to write: "In order to eliminate the bd confusion, an asymmetry must be introduced somewhere in the brain." In addition, recent results from functional magnetic resonance imaging show that the brain of people with dyslexia is not lateralized enough to perform certain functions. About 98% of the population uses the left hemisphere when reading. In people without reading defects (normal readers), asymmetries between the Maxwell centroids, i.e., between two small blue cone-free areas (about 100 micrometers in diameter) at the center of the two foveas, have been detected. On November 6, 2012, a patent for a device for detecting this asymmetry in normal readers was filed with the French National Institute of Intellectual Property (INPI) (Le Floch, Bourdillon, Ropars) (FR2997618). The lack of asymmetry was initially found in people with ocular instability problems, but it was not until 2017 that the first people with dyslexia were found to have a circular Maxwell center of mass, without asymmetry, with excessive mirrored or repeated images, causing visual confusion and making reading difficult (Le Floch A., Ropars G., 2017, Proc. R. Soc. B, https: / / doi.org / 10.1098 / rspb.2017.1380). However, the lack of asymmetry in people with dyslexia is not limited to the case of circular contours. In fact, in people with dyslexia, an asymmetry between two elliptical contours can be observed. However, this manuscript has an error on page 5, where it is written "and there is no preferred orientation angle φ for elliptical contours ( Figure 1 d)". Contrary to what was written in the 2017 paper, it is not enough to have two circular contours. In fact, a person with dyslexia may have two elliptical contours, but in this case the fundamental parameter is the orientation, which requires precise measurement. The aim of the present invention is to measure the orientation of the main axis of each eye, which should also help in early diagnosis in children. In fact, parents begin to suspect problems from the age of 4-5, which are often pointed out by teachers from kindergarten onwards, but are not confirmed until various reading tests carried out by speech therapists, especially around 8-9 years old. Therefore, the goal here is not to propose a device for measuring asymmetry, which determines the eye dominance of a person without problems, but to propose a device for comparing orientations, including in the case of a person with dyslexia and the presence of ellipses. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The invention will be better understood and other features and advantages will become apparent by reading the following description made with reference to the accompanying drawings, in which:

[0005] Figure 1 is a schematic diagram of the device architecture of a non-limiting embodiment of the invention, which comprises a unit UCM for controlling and measuring the basic parameters (mainly the orientation) of an ellipse projected by a projector P onto a bright screen E, and an aiming system V for an observer O with a double rotating filter FB (blue filter) and FV (green filter).

[0006] Figure 2 The relevant parameter to be measured is defined, namely the angle φ giving the orientation of the two main vertices A and B relative to the vertical. C and D are the secondary vertices of the ellipse, which also make it possible to measure the Defines the ellipticity. Determines the orientation of the principal axis of the right eye φ R and the orientation of the principal axis of the left eye φ L After that, the key is the difference φ R -φ L .

[0007] Figure 3 The case of a person with uncertain orientation and ellipticity difference (Δε=0) was measured.

[0008] Figure 4 The same ellipticity difference of zero was measured, but with equal "mirror" orientation, i.e. with opposite orientation (e.g. φ L =-40°,φ R =+40°).

[0009] Figure 5 The same orientation is measured with zero ellipticity difference, but with equal "translation" orientation, i.e. with parallel orientation (e.g. φ L =+40°,φ R =+40°). Summary of the invention

[0010] exist Figure 1 In the , the modules depicted are functional units, which may or may not correspond to physically distinguishable units. For example, some or all of these modules are combined together in a single component. On the contrary, according to other embodiments, some modules consist of physically separate entities. E denotes a screen illuminated with white light; P denotes a projector; UCM denotes a unit for controlling and measuring the orientation, ellipticity and elliptical surface of the Maxwell center of mass; V denotes an aiming system for an observer O; FB and FV denote a blue filter and a green filter, respectively.

[0011] Figure 2 All the parameters used in the present invention are introduced: the main vertices A and B determine the main axis and define the orientation φ of the ellipse outline for each eye, which is crucial here. The display on the device then records all the orientations φ R and φ L , that is, the corresponding orientations and differences of the two main axes of the right eye and the left eye.

[0012] The advantage is that Figure 1 The parameter controller schematically shown in can then be used to adjust the orientation of the principal axis of each eye to within 2° by means of an electronic card. The projector is arranged to illuminate the screen uniformly with white light, with a luminous flux of between 2000 and 4000 lumens.

[0013] Advantageously, the light beam is generated by one or more LED (light emitting diode) elements. Of course, the light beam can also be generated using other lighting elements, which in particular use LEDs of different colors (such as blue and green) to provide stable illumination to display the Maxwell centroid with high contrast.

[0014] Advantageously, the aiming system with rotating blue-green double filter uses a small electric motor to vary the frequency of rotation between 0.1 Hz and 1 Hz according to the needs of the observer. A distance of about 3 m from the aiming system to the screen creates a Maxwell centroid of about 3 cm in average diameter on the screen, enabling a proper superposition with the projected elliptical profile.

[0015] exist Figure 3 The device allows to observe and record the parameters of the most common cases, where in particular people with dyslexia show two quasi-circular Maxwell centroid contours, where φ R ,φ L and its difference Δφ=φ R -φ L is uncertain, and

[0016] Advantageously, the device makes it possible to identify Figure 4 distribution, which indeed corresponds to zero difference ellipticity ( and ), but the orientation of the principal axis relative to the vertical axis φ R and φ L is the opposite (mirror image) (φ R =-φ L ).

[0017] Advantageously, if Figure 5 As shown, the device can also be used to characterize and measure the interhemispheric projection repetition of non-translational symmetries. Here again, the ellipticity is indeed equal ( ≠ 1), but the device of the invention makes it possible to measure the orientation and parallelism of the main axes (φ) for any value of the orientation of the two profiles. R =φ L ).

[0018] The invention is not limited to the embodiments described above, but is applicable to any device making it possible to measure the Maxwell centroid orientation, including quasi-circular profiles that cause reading defects in particular in people with dyslexia, profiles with zero differential ellipticity but with opposite or parallel orientation of the main axes.

Claims

1. A device for measuring the possible ellipticity-dependent orientation of the blue cone-free Maxwell centroid of each eye of a person with dyslexia, characterized in that It includes: an electronic control and measurement system UCM, which creates an ellipse projected onto a screen with the orientation of the main axes adjustable to within 2°; The lighting system, which is approximately 2000 to 4000 lumens, illuminates the screen onto which the outline of the ellipse is simultaneously projected, marking and displaying the orientation of the main axes of the two eyes and their angular difference.

2. The device according to claim 1, characterized in that It comprises means for measuring and displaying the orientation of the major axes of two ellipses and their difference between two Maxwell centroids, in order to be able to define the type of dyslexia.

3. The device according to claim 1 and 2, characterized in that It makes it possible to measure the difference between the orientation of two ellipses of the left eye and the right eye with the same ellipticity but opposite orientation of the main axes within 2°, which leads to the first type of dyslexia.

4. The device according to claims 1, 2 and 3, characterized in that It makes it possible to measure profiles with the same ovality but with the main axes oriented parallel, which leads to a second type of dyslexia corresponding to the repetition of letters and words, especially for certain populations of people with dyslexia whose reading difficulties are caused by repetition.

5. Device according to any of the preceding claims, comprising a system including an optional colored LED system making it possible to display the Maxwell centroid and characterize the various asymmetric abnormalities mentioned herein, in particular for people suffering from dyslexia.

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