WO2004025352A1 - Pyramid sensor for determining the wave aberration of the human eye - Google Patents

Abstract

The invention relates to a sensor for determining the frontal wave aberration of the human eye, which uses a static crystal pyramid P as a nucleus. The invention is particularly suitable for use in the field of ophthalmology. The aforementioned pyramid P comprises four faces P' which divide the light beam into four parts, the intensity of which is recorded with a CCD camera or a similar intensity detector. The measurements are taken in a plane of the optical system (Fourier plane) and both the dynamic range and the sampling can be adjusted as required, such that the wave aberration function can be measured in multiple different conditions. The structure of the sensor can comprise a lens L1 which is used to form the Fourier transformation of the pupil function, a crystal pyramid P comprising four faces or facets P' which are used to divide and separate the electric field angularly into four parts and a second lens L2 which is used to join the output plane to a new plane in which the intensity sensor or CCD camera is positioned. While the measurements are being taken, the crystal pyramid P is maintained static and the field is made to oscillate around same.

Description

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OBJECT OF THE INVENTION

The present invention relates to a pyramidal sensor for measuring the wave aberration of the human eye. The sensor has the peculiarity that its core is materialized by a pyramid of four-sided dielectric material in order to divide the light that emerges from the reflection in the retina into four parts whose intensity is subsequently recorded with an intensity detector such as a CCD camera or other súnilar device.

It is an object of the invention to provide a sensor of the type referred to, with particular characteristics that allow both the signal obtained in response to the aberration value at each point and the spatial sampling of the wave aberration information to be dynamically adjustable, being useful for practical applications of the use of the information of the wave aberration function in the eye.

BACKGROUND OF THE INVENTION

The determination of wave aberration is critical in the design or improvement of optical systems. In the case of human eye optics, the knowledge of wave aberration enables the development of important practical applications, among which the following can be highlighted: Refractive surgery: Corneal ablation aims to reduce ocular wave aberration. The control of lasers that produce ablation is usually based on limited data (only blur and astigmatism) of the wave aberration. Potentially, laser control with precise measures of eye wave aberration could improve the results of the intervention. This perspective, in spite of being still in the study phase, has promoted the commercialization of wave aberration measurement systems,

10 mainly by the companies that manufacture refractive laser lasers. Directly related, although not involved in the control of lasers, there is a large potential market for systems dedicated to providing only wave aberration measures for evaluation.

15 ophthalmological pre- and post-surgical interventions.

Diagnosis in Ophthalmology: the use of adaptive optics techniques (dynamically changing optics) from the field of astronomy telescope construction in the human eye has been proposed.

20 The goal is to improve the retinal observation monsters. Obtaining more detailed images would directly increase the chances of early detection of retinal pathologies in previous stages of development when there is still the possibility of treatment.

25 If one takes into account that degenerative diseases of the retina are one of the most important causes of blindness in the developed world and that, as with other disabilities, they represent a significant economic expense, it is understood the interest in having every time better means

30 of diagnosis. Retinal imaging methods are based in ophthalmoscopes that are systems that produce images of the retina using the optics of the eye as part of the instrument itself. For this reason, the quality of the images they produce is limited by the aberrations of each patient's eye optics. The commercial success of a new generation of instruments of this type that, incorporating the dynamic correction of the wave aberration, offer greater resolution is assured. In this new generation of ophthalmoscopes, the detection of the

Wave aberration is a key piece since the control of the variable optics is carried out from this measurement. Phototherapy. Related to the previous point there is the possibility of applying Adaptive Optics to reduce the size of the laser light spot on the retina and thus improve

15- treatments of photocoagulation or localized activation of drugs by light. As before, wave aberration measurements are essential for system control. It is not difficult to foresee that this type of treatments, less invasive and, therefore, with more controlled effects, will increase in the

20 future.

Design of ophthalmic lenses (contact lenses, infraocular lenses, etc.). The development of new designs goes through the study of wave aberration in new prototypes. The current possibilities of machining optical materials

25 makes it possible to consider the individualized design of very precise corrective elements based on aberration data of each subject.

Ophthalmological evaluation systems of contact lenses or implants (intraocular lenses, etc.) to determine their effect

30 in vision. It is not difficult to foresee that each consultation of Ophthalmology will have a wave aberration measurement system for these tasks in the future.

Automatic refractometers are necessary devices in the field of optics for the determination of certain basic wave aberration (blur and astigmatism) in order to establish the correction.

Most of the wave aberration sensors that are marketed for ophthalmology applications, are based directly on the so-called microlens matrix or Hartmann-Sack sensor that provides indirect information of the wave aberration through local gradient values of the aberration of the wavefront.

There are documents corresponding to patents of invention that describe ways of measuring or determining wave aberration based on the type of sensor mentioned above, that is, Hartmann-Sack, a sensor that is currently the only one used in the eye for applications of adaptive optics

A drawback of the Hartmann-Sack sensor is that the dynamic range and sampling are fixed by the construction of the sensor itself, in particular by the focal and the opening of the microlenses, in addition its operation is based on a digital data processing (detection of mass centers in images) complicating the obtaining of wave aberration information.

In the Hartmann-Sack sensor the measurement is carried out in a plane conjugated with the exit pupil of the optical system to be evaluated while in the sensor object of this patent the measurement is carried out in a different optical system plane. DESCRIPTION OF THE INVENTION

The measurement system of the wave aberration, pyramid sensor, which is recommended, obtains the same type of information as the sensor

Hartmann-Shack referred to in the previous section, that is to say indirect information of the wave aberration through the gradient, although with variations that make the correct operation different.

More specifically, the sensor of the invention is based on an eye umumination system and a pyramid of four-sided dielectric material with a large angle between them whose purpose is to divide the light that emerges from the eye after reflection in the retina in four parts. The pyramid is placed in a plane external to the eye and conjugated with the retina (measurement plane) whose intensity is recorded behind with a CCD camera, or similar device, in a plane conjugated with the exit pupil of the system. To perform the first conjugation - retina with the plane of the pyramid - it may be necessary to use a lens or lens system. To perform the second conjugation - exit pupil plan with the intensity detector plane - a second lens or lens system is used.

Unlike what happens with the Hartrnann-Sack sensor described in the background of the invention, the measurement (plane of the pyramid) is performed in a plane conjugated with the plane of the pupua. The detector, CCD camera or simüar device, is placed in a plane posterior to the pyramid, conjugated with the plane of the eye exit pupil. This is different from what happens with the other sensor described in the background of the invention in which the intensity detection (CCD) is located in a plane conjugated with the plane of the retina.

In addition, compared to the Harrmann-Sack sensor described in the background of the invention, this system has the characteristic of that, with a pyramid of geometry and fixed dielectric properties, the sensor can be implemented in such a way that both the response and the sampling of the gradient information are dynamically modifiable, that is, they are adjustable, a characteristic that makes it different and especially interesting for applications in the human eye and for two reasons. First, given the great variability between subjects and even the possibility of finding subjects with pathologies that present large-scale wave aberrations, it is interesting to have sensors whose response is easily modifiable in such a way that saturation is avoided. Second, the dynamic alteration capacity of the parameters is interesting in dynamic systems such as adaptive optics in ophthalmology in which it may be convenient to dynamically modify the acquisition of data to adapt it to different aberration regimes in the system.

DESCRIPTION OF THE DRAWINGS

To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical implementation thereof, a set of drawings is attached as an integral part of said description. In an illustrative and non-limiting manner, the following has been represented:

Figure 1 shows the scheme of a wavefront sensor made in accordance with the object of the present invention.

Figure 2.- Shows a front view of the glass pyramid that is part of the sensor represented in the previous figure.

Figure 3.- Shows a different view of the sensor represented in Figure 1, with indices corresponding to four reflected pupils. Figure 4.- Shows with a) a linear oscillation path in the Fourier plane; with b) an extensive incoherent emitter with binary intensity is represented, and with c) the graph corresponding to the response for the linear and extended source of Figure 4 a) and b) is represented.

Figure 5.- It shows the scheme corresponding to a pyramidal sensor used with extensive illumination source, included as part of an optical system used to perform tests.

Figure 6.- Shows with a) image of the data acquired by the intensity detector; with b) the gradient in both orthogonal directions, and c) the computed phase of the pupil function represented module 2 according to the test performed on an artificial eye.

Figure 7 ^' .- Shows the variation of the different Zernike coefficients as the translation base is shifted in an artificial eye experiment, so that 1 cm of displacement introduces 0.97 diopters of refractive blur.

Figure 8.- Shows with a) the film of the acquired data, with b) the radiant in both orthogonal directions, and with c) the phase of the pupil function by moving the translation base (module 2) in a test performed In the living eye.

Figure 9.- Shows the variation of the different Zernike coefficients by moving the translation base in the live eye experiment.

PREFERRED EMBODIMENT OF THE INVENTION Figures 1, 2 and 3 schematize the elements of a pyramidal sensor. As shown in Figure 1, the lens (L is used to form the Fourier transform of the output pupil function of a generic optical system from which a collimated beam of light emerges. As shown in Figure 2, in This plane - a focal length apart from the lens and conjugated with the eye's retina - is placed in a pyramid of dielectric material (P) with four facets (P ') with a large angle between them, introducing four different inclinations, the pyramid Angularly divides and separates the light into four parts A second lens (L ₂ ) in Figure 1 is used to combine the exit plane of the eye of the optical system of the eye with a new plane in which a detector is placed intensity similar to a CCD As shown in Figure 3, if the system is free from aberration, without considering diffraction effects, the sensor acquires four copies of the aperture with binary intensity.If the system undergoes aberrations, all four Puppy images are not the same.

Figure 2 shows the crystal pyramid P with its four faces P '; while in figure 3 the sensor is shown, according to another different representation, with the indexes A, B, C and D corresponding to each of the images of the output pupil of the optical system under study.

The detailed operation is as follows. Without a beam that leaves a specific location of exit pupil does not suffer aberration, it reaches the origin of the Fourier plane. In this situation, it can be assumed that the pyramid divides the ray into exactly four equal rays each arriving at the sensor plane with the same relative location as shown in Figure 3. However, if the same ray undergoes aberration, it reaches the plane Fourier (plane where the pyramid is located) with coordinates given by

Where f is the focal length of the focusing lens, L _L in Figure 2, and w represents the function of the aberration wave at specific coordinates of the exit pupil (x, y). The ray then reaches only one of the four facets and therefore only contributes to the intensity in one of the four images of the pupua: only one of the four positions associated with the position of the emergent ray of the pupua will produce non-zero intensity. From this information it is possible to know the quadrant where the end of the gradient vector ^ w associated with the ray is located. However, this signal will be independent of the vector module. This situation can be understood as saturation whatever the aberration is as long as it is not null.

To avoid saturation, one solution is to darken the pyramid. The oscillation is carried out in such a way that the apex of the pyramid is translated along a symmetrical path around specific coordinates of the Fourier plane, not necessarily the coordinates of the optical axis, without rotation. While moving the pyramid, the CCD, or sensor simüar, must integrate the signal in the time that lasts a minimum cycle of oscillation. Thus, instead of being binary, the value of the four related pixels on the images of the four pupils is balanced according to the gradient module, that is, at the distance between the intersection of the beam with the Fourier plane and the center of oscillation By oscillating the pyramid, the signal for a specific set of four associated pixels in each of the four images of the output pupil is sufficient to calculate the coordinates 0 for each ray using the expressions

Where a, ₇ , b, and d represent the values of the pixels referenced as yj in the four pupils named as A, B, C and D as depicted in Figure 3.

Sampling (the density of gradient measurements) can be controlled by changing the scaling of the image of the system exit pupil on the plane of the CCD or similar detector. This can be achieved by modifying the focal length of the lens. This can be done dynamically using, instead of a single lens, a zoom like L ₂ . On the other hand, as indicated by equation (1), the sensor gain depends on the focal length f. The sensor response curve depends on the path followed by the apex of the pyramid. As an example, Figure 4 a) shows a simple linear path of amplitude. The apex of the pyramid, represented with a cross symbol, oscillates around the center of the Fourier plane. It is shown below, without loss of generality, what is the theoretical response for a particular beam of the sensor for a variation in the gradient that makes the intersection point of the beam move with the Fourier plane on the x-axis. In a cycle of oscillation the intensity of the pixel, j of the four reflected pupils is

Thus, using equation 2, the gradient is proportional to

The dotted line in Figure 4 b) shows the calculated response of the normalized sensor using equation (4). A change in the amplitude of the oscillation changes the gain and range. The sensor becomes saturated when an aberrated ray reaches the Fourier plane out of the path (outside the [-,] interval). At this point, it should be noted that the path does not necessarily have to be centered around the optical axis; Offset only means that the sensor measures a signal corresponding to a global inclination that is not present in the optical system under study. The linear trajectory used here is not the only possibility, other less simple but more practical trajectories are possible, as the circular effect will be to linearize the response.

According to one of the fundamental characteristics of the sensor, a system that moves the pyramid is equivalent to another in which the pyramid remains static and causes the electric field to oscillate around a point in the Fourier plane: for example using a system of mobile flat mirrors conjugated with some plane before the pyramid. The system response can be controlled by modifying the angular excursion of the mirrors.

In the event that the pyramid is used to determine the wave aberration of optical imaging systems in which it is possible to control the incident illumination such as the human eye there is an additional possibility. In this type of systems to achieve an emerging collimated beam the emitting source must be punctual. One way to oscillate the electric field over the pyramid is to swing the point source. As before, this type of system can be build using a system of movable flat mirrors in some plane prior to the entrance pupil of the optical system under study. The response of the system can be controlled, as before, by modifying the angular excursion of the mirrors. An alternative option to the previous ones is the following.

Consider the same optical system in Figure 1 by replacing the point emitter with an extensive incoherent source while the pyramid remains static with its vertex located at certain coordinates of the Fourier plane. In that case, assuming isoplanatism, the electric field in the Fourier plane can be considered with a set of indefinite copies of the electric field originated by a point source, inconsistent between them, transporting each different energies according to the distribution of the intensity of the fountain. The theoretical response of this system can be calculated by reusing the previous model by modeling the emitting object by infinite oscillation curves so that its area is filled. As a result, along with the incoherent emission, an additional restriction on the source appears: in order to preserve the symmetry of the sensor response with and the source must be symmetric.

Figure 4 b) shows an example of an extended single source based on the linear oscillation path of Figure 4 a), which consists of a flat emitting square of extension. For a ray, when the gradient value changes in the x direction, the theoretical value of the four associated pixels in the images of the four pupils can be calculated using the expression of equation (2) by integrating for.

'.y = d (Δ ² +2 Δ - ² ) Δ <<Δ 0 ξ> A

the following sensor response is obtained

1 ξ> A ξ = (2A - ξ) ξlA ² - Δ ≤ <Δ (VI)

- 1 ξ <-Δ

For a region where it is significantly smaller than, equation (6) can be approximated by

The answer is linear but the gain is doubled when compared to the case of the oscillating pyramid of equation (IV).

The solid line in Figure 4 b) represents the normalized response that was calculated using equation (VI) for this particular emitter source geometry. Although there is still a region with linear behavior, the linear response range is reduced compared to the case of the oscillatory pyramid. By adjusting the focal length /, or by changing the extent of the object, the measuring range of the gradient can be adjusted to the linear regime. In any case, if the signal were used to direct a wave aberration compensation device, it would not be mandatory to use the sensor only in the linear regime and the entire range would be usable.

If the source were ideally a one-dimensional incoherent emitter with the geometry of Figure 4 a) the answer would be the same as that obtained in the dotted line of Figure 4 b).

This especially simple extended source has been chosen for the benefit of clarity; it can be inferred that a simüar response can be found in other symmetric objects that do not necessarily have a constant intensity distribution.

A sensor equivalent to that which employs an incoherent symmetric emitting object is a system consisting of a point emitter and a diffuser or set of rotary diffusers located in a plane located between the plane of the exit pupil of the optical system under study and the plane of the piramid. The response range of such a system can be controlled by varying the distance between the diffusers thereby modifying the effect of the equivalent diffuser.

To test the previously described sensor consisting of a static pyramid and a source of extensive illumination, the electro-optical system depicted in Figure 5 was constructed. A laser was used as a source of illumination. A pair of independent rotary glass diffusers (RD) were used in order to randomly vary the phase. A lens system (LL ₂ ) and the beam splitter (BS) collects the light that emerges from the diffusers by lighting a large area of the retina. The effect of the rotary diffuser is to quickly change the mottling pattern

"speckle" in the retina. In a sufficiently long exposure time, it can be assumed that there is an incoherent extended emitting source with a Gaussian intensity profile on the retina.

The light that is reflected from the back of the eye passes through a Badal optometer (mirrors Mi, M ₂ , M ₃ and M4 and lenses L ₂ and L ₃ ) in whose M ₂ and M ₃ mirrors are mounted on a translation base allowing us to introduce or correct the blur when moving the base. After mounting Badal, the light passes through the lens L, which plays the role of lens Li in Figure 1. Then, the pyramid divides the beam and the lens L ₅ , equivalent to the lens L ₂ in Figure 1, produces a quadruplicate image of the pupil on the CCD detector. Finally, to control the size of the pup, an opening (A ₂ ) is placed in a plane conjugated with the natural pupil of the eye.

The images obtained are processed as follows.

First, an image processing module was developed to find the central coordinates of the four images of the output pupil. This calculation should be done only once at the beginning of the measurements. The obtained pupil coordinates are used to create four images, each of which corresponds to the matrices A, B, C and D

(see figure 3). After calculating equation (2) the computer calculates the phase from the gradient data using an application of the Singular Value Decomposition (DVS) algorithm to calculate the pseudo-inverse matrix. Finally, the program produces the wave aberration expressed in coefficients of the Zernike expansion excluding the piston, since the sensor is not sensitive to this term, and the lateral displacements of the wavefront, since we do not have precise control of the transverse position of the apex of the pyramid. The latter is just a limitation of this particular assembly that can be easily solved by precisely controlling the position of the pyramid's vertical.

It should be noted that, after the calculation for the first image has been made, the integration for subsequent images implies only a multiplication of matrices which implies that the computer loses a very small fraction of time in the processing of the detector signals. This makes this sensor suitable for mediated Extremely fast wave aberration.

Lacking precise control over the extent of the source in the retina, we cannot assume an increase in slope. Therefore, we calibrate the system using a parameter obtained by means of a comparison of the measured blur coefficient with the real value that a specific displacement of the translation base must produce.

We tested the system in an artificial eye that was built using a short focal lens to simulate the eye's optics and a static diffuser as a retina. We move the optometer translation base by measuring wave aberration at intervals. The translation base offset basically introduces an amount of blur proportional to the offset. Figure 6 a) shows the images acquired by the CCD; b) shows the gradients calculated in the two orthogonal directions and c) the computed phase of the pupil function represented in turn (module 2). The software has no limit on the number of Zernike coefficients it can handle; We arbitrarily limit the number to twelve coefficients.

Figure 7 shows the behavior of the different Zernike coefficients using the order and normalization given by Noli expressed in microns as a function of the different locations in the translation base. The sensor produces a linear response in the measured blur for controlled values of the induced blur in the system. We use this result to find the sensor response to the local gradient. The signals that the sensor measures at the different locations of the pixels within the pupil (Figure 6b) are proportional to the corresponding local variation of the wavelength aberration, that is, the measured gradients are located at the linear response regime of the sensor of figure 4 (continuous line). It is important to note that this behavior does not imply any concrete mode but the response of the sensor to the local gradient. It can then be assumed that the sensor is capable of providing the correct value of the coefficient for any Zernike mode that is present on the wavefront whenever sampling is sufficient. The same analysis could be carried out using a controlled change in any other different Zernike mode; the blur was the most easily controllable aberration to introduce into our experiment. The results in Figure 7 show some variation in higher coefficients not correlated with the blur. Since the sensor responds with virtually no deviation for a linear response for blurring, we assume that the values for other non-spurious coefficients, but were also present in the system and changed slightly for each position of the translation base due to some alignment Defective Badal optometer lenses.

It should be noted that if the sensor has to be used for the absolute measurement of the aberration value, and not to direct an adaptive optics system, the local gradients must be placed within the framework of the linear response. For higher gradient values the sensor signals must be corrected using not a constant, but the complete information of the response curve. Alternatively, as stated above, the extent of the source in the retina can be modified to increase the linear frame. However, it can be seen that, in this particular optical system, the sensor shows a linear response for a gradient frame suitable for applications in the human eye with high sampling rate: approximately eight mü data points of the frontal wave inclination for a pupil diameter of 4 mm. Performed the experiment in the human eye, the results were as follows:

In the previously used system we include a teether consisting of a dental imprint attached to a positioning system to fix the subject's head. We collected images with exposure of 200 msec and 4 mm in diameter of pupua. The area illuminated in the retina was approximately 1 degree. The subject observed a target to establish fixation between exposures. The accommodation was not paralyzed. As was the case with the artificial eye, the experiment consisted of acquiring sequential images for different displacements of the translation base by observing the behavior of Zeπüke coefficients. Figure 8 shows an example of the pupil plane images collected by the CCD (panel a); in panel b) the gradients calculated using the images in panel a), c) the wave aberrations obtained.

Figure 9 shows the variation of the first twelve Zernike coefficients in relation to the displacements of the translation base made. The behavior is very similar to that of the artificial eye: a linear response to changes in the blur while the other techniques remain stable. In this figure, the blur response shifts to the right, representing the refraction of the subject (approximately half diopter). The greater variability in the value of the coefficients found in the living eye (figure 9) compared with the artificial eye (figure 7) is explained by different factors such as, among others, that the accommodation was not paralyzed and that the position and alignment The subject's eye may be slightly different during successive CCD acquisitions. It can be seen that the eye has astigmatism (Z ₆ ) mainly because the fixation point was not aligned with the axis of the optical system.

Claims

 R F, T V T N D T C A C I O N F, S ^I-.- sensor pyramidal for determining the wave aberration of the human eye comprising, as core, a pyramid of dielectric material P static four - sided P 'with an angle large vertex between the faces, by that the angular distribution of the beam of light is carried out in four parts, the intensity of which is recorded with a detector similar to a CCD detector; having planned the possibility of using a first lens, or system of lenses and / or mirrors, L _t located in front of the pyramid P to form the Fourier transform of the pupil exit function of the eye, while behind the pyramid P is located a second lens, or system of lenses and / or mirrors, L ₂ to conjugate the plane of the exit pupil of the eye on a plane in which the aforementioned intensity detector is located. 2 .- pyramidal sensor for deteπninación of wave aberration of the human eye according ^to claim I, wherein a collimated light beam is static Üuminar utüiza to the eye; having provided a system of movable flat mirrors, both conjugated with the eye exit pupil and simulated between the eye and the pyramid, in such a way that they make the emerging light of the eye oscillate on the pyramid P so that the beam follows a circuit symmetrical with respect to some point of the plane where the pyramid is located. 3 .- pyramidal sensor for determining the wave aberration of the human eye, according ^to claim I and 2, in which the response of the sensor is modified by dynamically varying the amplitude of angular oscüación mirrors. 4 .- pyramidal sensor for determining aberration wave human eye or other optical system according to claim I ^to, wherein a collimated light is made oscüar angularly to üuminar the eye or, in general, the optical system under study so that the reflected light is utüiza by the eye or, in general, that crosses the optical system under study obscure over the pyramid P following a symmetrical circuit with respect to a point on the plane where the pyramid is located; a system of movable flat mirrors, located between the source of Üurnination and the entrance pupil of the eye or, in general, the optical system under study and both conjugated with this plane, is provided in such a way that they oscillate angularly the beam of illumination . 5 ^a Pyramidal sensor for the determination of the wave aberration of the human eye or other optical system, according to claim I ^a and 4 ^a , wherein the sensor response is dynamically modified by varying the angular oscillation amplitude of the mirrors. 6 .- Sensor pyramidal for determining the wave aberration of the human eye, or any other optical system according to claim Ia, wherein a light source extensive is utüiza approximately spatially incoherent to üuπiinar the optical system is to be determined so that the beam reaches the plane where the pyramid P is located with an extension greater than if the source of illumination were punctual. 7 ^a .- Pyramidal sensor for the determination of the wave aberration of the human eye, or any other optical system, according to claim I ^a and 6 ^a , in which the sensor response is modified by varying the apparent or real extent of the source of illumination. 8 .- pyramidal sensor for determining aberration wave human eye according to claim Ia, wherein a collimated light utüiza to illuminate the eye as a set of planes diffusers used (frosted glass or simüar) on a backplane to pupüa exit the eye and before the pyramid P to extend the beam on this plane. 9 .- Sensor pyramidal for determining the wave aberration of the human eye, or any other optical system according to claim I ^to and 8, characterized in that the distance between diffusers is controlled mechanically to modify the optical properties of the diffuser system in order to vary the extent that they induce in the beam on the pyramid P and thereby dynamically adjust the sensor response. 10 .- ablation procedures custom refractive surgery employing the pyramidal sensor according to previous claims. 11 ^a .- Design procedures for custom infraocular lenses and ophthalmic lenses in general that employ the pyramidal sensor according to claims I ^a to 9 ^a . 12 .- intraocular lenses and ophthalmic lenses in general for customized design which has been used the pyramidal sensor according ^to claims I to 9. 13 .- Systems retinal image using adaptive optics controlled by a pyramidal sensor according ^to claims 1 to 9.