RU2600854C2 - Ophthalmic wave front sensor, operating in parallel sampling and synchronous detection mode - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: ophthalmic wave front sensor comprises: light source; first light-guiding element; first optical wave front relay system; matrix of two-dimensional position recording devices; and matrix of extraction partial wave front elements located before two-dimensional matrix of position registration devices. Each two-dimensional position recording device is configured to detect value of two-dimensional image spot centroid deviation from reference position and output measuring signal indicating value of two-dimensional deviation. Each element of selection in matrix elements of partial selection of wave front is made with possibility of partial selection of wave front of relay of wave front and focusing of selected partial wave front on corresponding two-dimensional device for recording position in matrix of two-dimensional position registration devices. At that, sampling elements partial wave front physically spaced apart so that each selected partial wave front of wave front, reflected from eye, is focused only on corresponding two-dimensional device for recording position corresponding to element of selection of partial wave front. Another version of ophthalmic wave front sensor package assumes scanner/deflector beam arranged along beam path, made with possibility of full capture and scanning beam relay wave front.

EFFECT: using given group of inventions will allow to continuously measure refraction eye conditions.

24 cl, 10 dwg

Description

RELATED APPLICATIONS

[0001] This application claims priority to US patent application 13 / 459,914 entitled "Ophthalmic Wavefront Sensor Operating in Parallel Sampling and Lock-In Detection Mode", filed April 30, 2012, which is a partial continuation of US patent application 13 / 198,442 under titled “A Large Diopter Range Real Time Wavefront Sensor”, filed August 4, 2011, which is a partial continuation of application No. 12 / 790,301, entitled “Adaptive Sequential Wavefront Sensor With Programmed Control,” filed May 28, 2010, which is the application , selected from application No. 11 / 761,890 under the name "Adaptive Sequential Wavefront Sensor and its Applications", filed June 12, 2 007, now US Patent No. 7,815,310, issued October 19, 2010, which is a partial continuation of patent application No. 11 / 335,980, entitled "Sequential Wavefront Sensor", filed January 20, 2006, now US Patent No. 7,445,335, issued November 4 2008, and this application is also a partial continuation of application No. 13 / 154,293, entitled "A Compact Wavefront Sensor Module and Its Attachment to or Integration with an Ophthalmic Instrument", filed June 6, 2011, which are all incorporated herein by links for all purposes.

FIELD OF THE INVENTION

[0002] One or more embodiments of the present invention relate, in general, to wavefront sensors for determining the refractive state and aberrations of the wavefront of the eye. In particular, the invention provides a device for determining the refractive state and aberrations of the wave front of the eye during an ophthalmic operation.

BACKGROUND

[0003] Wavefront sensors are devices used to measure the shape of the wavefront of light (see, for example, US4141652 and US5164578). In most cases, the wavefront sensor measures the deviation of the wavefront from the reference wavefront or an ideal wavefront, such as a plane wavefront. The wavefront sensor can be used to measure aberrations of both low orders and high orders of various optical imaging systems, for example, the human eye (see, for example, US6595642; J. Liang, et al. (1994) "Objective measurement of the wave aberrations of the human eye with the use of a Hartmann-Shack wave-front sensor, "J. Opt. Soc. Am. A 11, 1949-1957; T. Dave (2004)“ Wavefront aberrometry Part 1: Current theories and concepts ”Optometry Today, 2004 Nov. 19, pp. 41-45). In addition, the wavefront sensor can also be used in adaptive optics in which the distorted wavefront can be measured and compensated in real time, using, for example, an optical wavefront compensation device, for example, a deformable mirror (see, for example, US6890076, US6910770 and US6964480 http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=6890076.PN.&OS= = PN / 6890076-h0 # h0http: //patft.uspto.gov/netacgi/nph-Parser? Sect1 = PTO1 & Sect2 = HITOFF & d = PALL & p = 1 & u =% 2Fnetahtml% 2FPTO% 2Fsrchnum.htm & r = 1 & f = G & l76 PN. & OS = PN / 6890076 & RS = PN / 6890076-h2 # h2). As a result of such compensation, a sharp image can be obtained (see, for example, US5777719).

[0004] The term “phakic eye” means an eye including its natural lens, the term “aphakic eye” means an eye where its natural lens is removed, and the term “pseudophakic eye” means an eye with an implanted artificial lens. Currently, most wavefront sensors for measuring the aberration of the human eye allow you to cover only a limited range of optical power from about -20 diopters to +20 diopters for a phakic or pseudophakic eye. In addition, they are also designed to operate in a relatively dark environment when it is necessary to measure the wavefront of the eye.

[0005] During ophthalmic operations that affect refraction, it is desirable to know the refractive condition of the eye throughout the operation to provide continuous feedback to the surgeon (see, for example, US6793654, US7883505 and US7988291). This is especially important in the case of cataract surgery, in which the natural lens of the eye is replaced by a synthetic lens. In this case, the surgeon prefers to know the refractive state of the eye at the phakic, aphakic, and pseudophakic stage to select a synthetic lens, to confirm that its refractive ability meets the requirements after removing the natural lens, and also to confirm emmetropia or other intended values of optical power after synthetic implantation the lens. Thus, there is a need for a wavefront sensor capable of covering a wider range of measurement of optical power and also allowing the surgeon to measure the refractive state of the eye with a given degree of accuracy, not only in the phakic and pseudophakic state, but also in the aphakic state.

[0006] In addition, during an ophthalmic operation, the eye is illuminated with unpolarized broadband (white) light from a surgical microscope so that the surgeon can see the patient’s eye through the microscope. This illuminating light is also directed into the patient’s eye, scattered on the retina and returned to the surgical microscope. The wavefront sensor connected to the surgical microscope receives both the returned wavefront measurement light intended for it and the broadband illumination from the surgical microscope. A microscope illumination light source is generally not intended to create a sufficiently small effective light source on the retina that is required to generate a wavefront that reveals the patient's refractive state. For this reason, any light from a surgical microscope, perceived by the wavefront sensor, can lead to incorrect information about the refractive condition of the patient. Thus, there is also a need for an ophthalmic wavefront sensor that is not affected by light from a surgical microscope.

[0007] Commercially available wavefront sensors for cataract surgery, such as the WaveTec Vision intraoperative wavefront aberrometer from WaveTec Vision (see, for example, US6736510), do not provide continuous feedback, have a limited range of refractive power and are also subject to interference in the form of illumination light surgical microscope. In fact, in order to obtain a sufficiently accurate and reliable measurement of refraction using an ORange wavefront sensor, the surgeon must suspend the surgery, turn off the light of the surgical microscope and capture multiple data frames, which leads to an additional increase in cataract refractive surgery time by several minutes.

SUMMARY OF THE INVENTION

[0008] One embodiment of the invention provides an ophthalmic wavefront sensor comprising a light source configured to receive a reference signal oscillating / pulsating at a reference frequency and generating a beam of light formed by light pulses at a reference frequency, a light guide element configured to start a light beam from a light source into the patient’s eye, and where the part of the light beam returning from the patient’s eye forms an object wavefront in the form of light pulses frequency, an optical wavefront relay system configured to relay an object wavefront from an object plane located in front of the patient’s eye to the image plane of the wavefront along a beam path that can direct a relay wave of an incident wavefront having a large optical power range on the object plane, to the plane of the wavefront image, a matrix of position recording devices with a high-frequency characteristic, and each device The position registration property is configured to detect the deviation of the centroid of the image spot from the reference position and output a measurement signal indicating the deviation, a matrix of partial wavefront selection elements located up to the matrix of position recording devices with a high-frequency characteristic and, essentially, in the image plane of the wave front, and each selection element in the matrix of elements of the selection of the partial wave front is configured to select the partial wave a new front of the relayed wavefront and focusing the selected partial wavefront on the corresponding position recording device with a high-frequency characteristic in the matrix of position recording devices with a high-frequency characteristic, where the partial wavefront selection elements are physically spaced from each other so that each selected partial wavefront of the object wave front with a high optical power range focuses only on the corresponding device reg position tracing with a high-frequency characteristic corresponding to a partial wavefront selection element and an electronic frequency-sensitive detection system connected to receive a reference signal and a measurement signal, the electronic frequency-sensitive detection system being configured to indicate only the magnitude of the frequency component of the measurement signal close to reference frequency, which allows you to essentially suppress all noise signals, for example, 1 / f noise, at frequencies different from the reference th frequency.

[0009] One feature is the use of two cascade-connected wavefront repeaters, the second repeater having a Fourier transform plane, where the wavefront relay beam is limited to a certain amount of space when the wavefront from the eye varies over a wide range of optical power. The beam scanner / deflector is located in the Fourier transform plane of the second repeater for angular scanning of the beam, so that the relayed wavefront in the image plane of the final wavefront can be laterally shifted relative to the matrix containing a number of partial wavefront selection elements. The corresponding number of PSDs is located behind the wavefront selection elements for operating in the synchronous detection mode synchronously with the pulsed light source, which generate the wavefront from the eye. The transverse shift of the wavefront allows you to select any part of the relayed wavefront and also allows you to flexibly control the spatial resolution of the selection of the wavefront.

[0010] Another sign for use during an ophthalmic operation is a light source for generating a wavefront, the output of which varies between at least two states, the wavefront returning from the patient’s eye is detected in each of the “bright” states and “Dark” state so that you can filter out signals from light other than the measuring light.

[0011] Another feature is the parallel detection of parts of the wavefront using a number of high-speed PSDs that can all work in synchronous detection mode synchronously with the light source at a frequency above the 1 / f noise range so that zero and low background noise can be effectively filtered out. frequencies.

[0012] Another feature is the implementation of active parallel selection of the wavefront. Elements of active, parallel wavefront selection can be controlled with respect to their position, size of the partial wavefront selection aperture, focusing force, and on / off state.

[0013] Another feature extends the range of optical power due to the presence of partial wavefront sampling elements spaced wide enough to exclude mutual interference between wavefront sampling elements in a large optical power range for measuring refractive error. In another example, only a certain number of partial wavefronts, sufficiently separated from each other, are selected by activating a subset of the partial wavefront selection elements, and also because only the corresponding number of position recording devices / detectors (PSDs) can avoid mutual interference. In yet another example, PSDs and partial wavefront selection elements can be activated to accordingly change their longitudinal position and / or their focusing force in accordance with the refractive state of the patient, which allows you to dynamically adjust the sensitivity of each PSD to the slope of the partial wavefront. In addition, the transverse position of the PSD can be adjusted according to the refractive condition of the patient, so that each PSD is located in the best transverse position to provide an optimized characteristic of the centroid position.

[0014] Another feature is the use of sequential scanning or shifting the wavefront as a whole so that any part of the incident wavefront can be selected, while the elements of the parallel selection of the partial wavefront and the device / detector position registration (PSD) have a fixed position in space. In another aspect, the scanner / deflector tracks the eye and shifts the wavefront returning from the patient’s eye, automatically adjusting the shift so that, depending on the size of the pupil, the position and the optical power of the wavefront from the eye, select only certain desired parts of the wavefront in the pupil of the patient, for example, in the central region with a diameter of 3 ~ 4 mm.

[0015] Another feature is the use of regular reporting of measured eye refraction in the sense that there is a small delay between any change in refractive state and the report on it provided by the device. This is achieved by averaging the detected wavefront aberration data over the desired period and updating the result of the qualitative and / or quantitative measurement superimposed on the operative image of the eye with the desired refresh rate.

[0016] Another feature provides accurate measurements within a wide range of the optical power of refractive errors that occur during an ophthalmic operation, for example, disorders that occur after removal of the natural lens of the eye, but before it is replaced with an artificial lens. These accurate measurements can be achieved in various ways. One example is the construction of optics for dynamically adjusting the sensitivity or slope of the partial wavefront slope characteristic curve by actively changing the distance between the partial wavefront selection elements and position recording devices / detectors or by actively changing the focal length of the partial wavefront focusing lenses. Another example is the dynamic displacement of the value of the spherical refractive power of the wavefront on the conjugate plane of the image of the intermediate wavefront using the displacement element of the value of the spherical optical power, for example, a lens with a variable focal length.

[0017] These and other features and advantages of illustrative embodiments will become more apparent to those skilled in the art upon reading the following detailed description of preferred embodiments given in conjunction with the accompanying drawings. Each of these features can be used individually or in conjunction with any of the embodiments described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a diagram of a serial wavefront sensor disclosed in US7445335, owned by the same copyright holder.

[0019] FIG. 2 is an improved optical configuration disclosed in US20120026466 belonging to the same copyright holder.

[0020] FIG. 3a is one embodiment of an exemplary wavefront sensor in which a pulsed light source is synchronized with an array of position recording devices / detectors so that the sensor can operate both in parallel sampling mode and in synchronous detection mode.

[0021] FIG. 3b is an array of elementary lenses of a typical Shack-Hartman wavefront sensor with a corresponding array of position recording devices / detectors and a maximum range of optical power measurement that can be achieved without mutual interference.

[0022] FIG. 3c is an illustrative configuration of partial wavefront sampling elements with a corresponding array of position recording devices / detectors and a maximum optical power measurement range that can be achieved without interference.

[0023] FIG. 4 is a block diagram showing one illustrative embodiment of a synchronous detection amplifier.

[0024] FIG. 5 is one example of sequential transverse shear or wavefront scanning with respect to the optical configuration shown in FIG. 3a.

[0025] FIG. 6 is another embodiment of the wavefront sensor shown in FIG. 3a, in which the configuration of the 8-f wavefront repeater is combined with a small beam scanner to provide practical sequential scanning of the wavefront in addition to parallel wavefront selection and synchronous detection.

[0026] FIG. 7 is one example of a sequential transverse shear or wavefront scan applied to the optical configuration shown in FIG. 6.

[0027] FIG. 8 is an example of incorporating a fixation light source and an eye image sensor into the configuration shown in FIG. 6.

[0028] FIG. 9 is an example of integration of a wavefront sensor disclosed herein with a surgical microscope.

[0029] FIG. 10 is an example of integration of a wavefront sensor disclosed herein with a slit lamp biomicroscope.

DETAILED DESCRIPTION

[0030] Turning to the discussion of various illustrative embodiments presented in the accompanying drawings. Although the following description is provided in connection with these embodiments, it should be understood that it is not intended to limit the invention to any embodiment. On the contrary, it is intended to cover alternatives, modifications and equivalents that may be included in the essence and scope of the invention defined by the following claims. In the following description, numerous specific details are set forth in order to provide a thorough understanding of various embodiments. However, the present invention can be practiced without some or all of these specific details. In other cases, well-known process operations are not described in detail in order to avoid difficulty in understanding the present invention due to unnecessary details. In addition, each occurrence of the expression “exemplary embodiment” at various places in the description of the invention does not necessarily refer to the same illustrative embodiment.

[0031] Most conventional wavefront ophthalmic sensors for measuring the wavefront of the human eye use a two-dimensional CCD or CMOS image sensor to collect wavefront information. For example, a typical Hartman-Shack wavefront sensor (see, for example, US5777719, 6199986 and 6530917) uses a two-dimensional array of elementary lenses and a two-dimensional image sensor based on a CCD or CMOS. The Scherning wavefront sensor (see, for example, Mrochen et al., "Principles of Tscherning Aberrometry," J of Refractive Surgery, Vol. 16, September / October 2000) projects a two-dimensional dot matrix image onto the retina and uses a two-dimensional CCD-based image sensor or CMOS to obtain an image of a two-dimensional bitmap returned from the eye to extract wavefront information. The Talbot wavefront sensor uses a cross-grating and an CCD or CMOS image sensor located on the self-image plane of the cross-grating (see, for example, US6781681) to extract wavefront information. Talbot’s moiré wavefront sensor (see, for example, US6736510) uses a pair of cross-gratings rotated relative to each other at a certain angle, and a CCD or CMOS image sensor to obtain an image of the moire pattern to extract wavefront information. The phase-front wavefront sensor (see, for example, US7554672 and US20090185132) uses a diffractive lens element and a two-dimensional CCD or CMOS image sensor to obtain images associated with different diffraction orders to extract wavefront information.

[0032] Due to the large amount of data that a two-dimensional image sensor must collect, and the frame rate limitations due to the clock speed and / or data transfer speed of an electronic data transfer line, such as a USB cable, image sensors used in all of these traditional wavefront sensor devices can only operate at a relatively low frame rate (usually 25 to 30 frames per second) and, therefore, are sensitive to zero or low frequency background noise. As a result, these conventional wavefront sensors can, in general, only function in a relatively dark environment to reduce noise from background / ambient light of zero or low frequency.

[0033] In addition, the measurement range of the optical power of these ophthalmic wavefront sensors is generally limited to ± 20 diopters, for the most part, due to a compromise in the spacing or spacing of a fixed grid of wavefront selection elements that determines the sensitivity to wavefront tilt, the range of measurement of the optical power of the wavefront and the spatial resolution of the measurement of the wavefront.

[0034] Another wavefront sensor technology based on laser beam tracking (see, for example, US6409345 and US6932475) does not necessarily require the use of a two-dimensional CCD or CMOS image sensor to extract wavefront information. However, a commercial product (iTrace from Tracey Technologies) has a limited measurement range of only ± 15 diopters and still requires a dark environment to measure the wavefront.

[0035] US7445335, which belongs to the same applicant, discloses a serial wavefront sensor that sequentially shifts the entire wavefront so that only the desired portion of the wavefront can pass through the wavefront selection aperture. This wavefront sensor employs synchronous detection to remove zero or low frequency optical or electronic noise, for example, from background light or electronic noise caused by the pulsation of the light source used to generate the wavefront from the eye, and synchronizing it with a position recording device / detector with high frequency response (e.g., square detector). Thus, this wavefront sensor does not require a dark environment for measuring the wavefront and is very suitable for continuous intraoperative refractive surgery in real time, where the light from the surgical microscope always remains “on”. Sequential selection of the wavefront completely removes any potential problems of mutual interference, which, thus, provides the possibility of a large dynamic range of measurement of the wavefront. However, the optical configuration presented in US7445335, is not ideal for covering a wide range of optical power, because it needs a beam scanner with a relatively large area of the interception of the beam. Another U.S. patent application (US20120026466) discloses optical configurations improved over US7445335. These advanced configurations allow the use of a relatively small and commercially available light beam scanner (for example, a MEMS-based scanner) to scan the entire object beam from the eye within a wide range of optical power (up to ± 30 diopters), and therefore it is possible to adequately capture eye refraction even in aphakic condition. Due to the flexible shift of the wavefront, it is possible to select any part of the wavefront and, thus, achieve high spatial resolution.

[0036] However, due to eye safety requirements, the limit of optical energy that can be delivered in a given time into the patient's eye can be set. Thus, even with a pulsating light source and using the synchronous detection approach to increase the signal-to-noise ratio, if a large number of spatial portions of the wavefront returned from the eye are required, the refresh rate of the wavefront measurement can be limited. On the other hand, if it is desired to ensure a high refresh rate of the wavefront measurement, the maximum number of spatial selection points may be limited. Thus, it is necessary to further increase the performance of such a wavefront sensor operating in the synchronous detection mode.

[0037] In accordance with one or more embodiments of the present invention, a number of parallel wavefront sampling elements are combined with a corresponding number of image position / light spot (PSD) devices / detectors that all operate in synchronous detection mode in synchronization with the pulsation of the light source at a frequency above the frequency range 1 / f noise. Each PSD has a high enough frequency response so that noise generated by zero or low frequency background light can essentially filter out and increase the signal-to-noise ratio.

[0038] In addition to the parallel selection of the wavefront, the physical spacing of the elements of the parallel selection of the wavefront is set so that there is no mutual interference in the desired range of optical power of the refractive disturbance of the eye. In addition, to select any part or segment of the wavefront, the wavefront can also be sequentially shifted relative to the wavefront selection elements using approaches similar to those disclosed in US7445335 and US20120026466 belonging to the same applicant.

[0039] FIG. 1 is a schematic diagram of a serial wavefront sensor disclosed in US7445335 belonging to the same applicant. A narrow beam of light from the light source 134 is directed to the retina of the eye 138 through the light guide element 136, for example a beam splitter. The object beam of light emanating from the retina of the eye, having a wavefront 102 when exiting the eye, is focused by the first lens 104. The object beam of the wavefront propagates through a polarizing beam splitter (PBS) 106 positioned in such a way that its transmission polarization direction is aligned with the desired polarization direction of the object light beam. As a result, the linearly polarized object beam will pass through the PBS 106. The quarter-wave plate 108 is located behind the PBS 106, and its axis of maximum speed of light propagation is oriented so that after the beam passes through the quarter-wave plate 108, a circularly polarized light beam is obtained.

[0040] An object light beam that carries wavefront information from the eye is focused on the reflective surface of the oblique scanning mirror 112, which is mounted on the motor spindle 114. The object light beam reflected by the mirror acquires a direction that depends on the angle of inclination of the scanning mirror 112 and the rotational position of the electric motor 114. The reflected beam still has circular polarization, but the circular polarization changes the direction of rotation from left to right or from right to left. Therefore, after passing through the quarter-wave plate 108 a second time on its return path, the beam again becomes linearly polarized, but its direction of polarization rotates 90 degrees relative to the direction of the original incoming object beam. Thus, on the polarization beam splitter 106, the returned object beam will, for the most part, be reflected to the left, as shown by the dashed light rays in FIG. one.

[0041] A second lens 116 is located to the left of PBS 106 to collimate the reflected object beam and to create a copy of the original input wavefront (124) in the plane of the wavefront aperture 118. Due to the tilt of the scanning mirror, the duplicated wavefront 124 is shifted in the transverse direction. Aperture 118 is located in front of the partial wavefront focusing lens 120 to select a small portion of the duplicated wavefront 124. The partial wavefront focusing lens 120 focuses the selected partial wavefront onto a position recording device / detector 122, which is used to determine the centroid of the focused light spot generated from sequentially selected partial wave fronts. By rotating the motor 114 and changing the angle of the scanning mirror 112, the radial and azimuthal shift of the duplicated wavefront can be controlled so that any part of the duplicated wavefront can be selected for sequential transmission through aperture 118. As a result, the entire wavefront of the original incoming beam can be characterized as in the case of a standard Hratman-Shack wavefront sensor, except that the centroid of each partial wavefront Now it turns out sequentially, but not in parallel.

[0042] As can be seen in FIG. 1, by controlling the angle of inclination of the scanning mirror and the pulsation frequency of the light source, any part of the wavefront can be selected. In addition, the electronic control and detection system can synchronize the operation of the light source 134, the motor 114, the wavefront selection aperture 118, if it is also active, and the position detection detector 122 to provide synchronous detection. Thus, it is possible to increase the signal-to-noise ratio and filter out the noise generated by the background light of zero or low frequency.

[0043] However, when the wavefront shift is carried out by the beam scanner on the optical Fourier transform plane of the 4-f wavefront relay optical system, when the value of the disturbance of the refractive power of the patient’s eye is large, the size of the object beam in the Fourier transform plane will also be relatively large. This means that in order to cover a wide range of optical power, the beam scanner needs a relatively large area of beam capture. In the case of cataract surgery, where the working distance between the eye and the input port is large, the required size of the beam scanner will be impractical in terms of cost and commercial availability.

[0044] FIG. 2 shows another optical configuration disclosed in US patent application US20120026466, which uses two cascade-connected 4-f repeaters having first and second Fourier transform planes, A and C, respectively, and first and second image planes, B and D, respectively . By using two cascaded 4-f wavefront repeaters or an 8-f wavefront repeater, a consistent transverse shift of the wavefront can be achieved by angular scanning the wavefront beam on or around the second Fourier transform plane C, where the wavefront beam width (over the desired large range refractive errors) can be maintained in a certain range of physical dimensions so that a relatively small beam scanner 212 can completely intercept the object beam.

[0045] As shown in FIG. 2, after the first wavefront repeater in the wavefront image plane B, the width of the object beam decreases due to the difference in focal length between the first lens 204 and the second lens 216, although the divergence or convergence of the beam increases. The second 4-f wavefront repeater comprises a third lens 240 and a fourth lens 242, each of which has a relatively large focusing power or small focal length and a relatively large numerical aperture (NA) or beam cone angle. The beam width in the second plane C of the Fourier transform is now relatively small. Angular scanning of the beam in the second plane C of the Fourier transform allows you to transversely shift the image of the wavefront in the second plane D of the image of the wavefront. A transversely shifted wavefront can be selected on the second plane D of the wavefront image using the wavefront selection aperture 218 and focused using a partial wavefront focusing lens 220 onto a position recording device / detector 222 (PSD).

[0046] Similarly to the embodiment shown in FIG. 1, by controlling the beam scanner 212 in the second Fourier transform plane C and adjusting the temporal mode of the pulsation of the light source, any part of the wavefront can be selected. Again, the electronic control and detection system can synchronize the operation of the light source 234, scanner 212, aperture 218 (if it is a variable aperture) and PSD 222 to provide synchronous detection to increase the signal-to-noise ratio and filter out the noise generated by zero or low frequency background light .

[0047] An electronic control system 236 having a control user interface 238 is connected to a beam scanner 212 and a variable aperture, allowing these elements to be controlled to change the scan pattern or aperture size. In other embodiments, the electronic control system 236 may be connected to other controlled elements, which will be described in more detail below. The user interface 238 can be made in the form of buttons on the device, a graphical user interface (GUI) on the device or on a computer connected to the electronic control system 236.

[0048] Note that in FIG. 1 and 2, only one wavefront selection element and only one position recording device are shown, and wavefront selection is carried out only sequentially. In this case, only one part of the entire wavefront is selected, which does not allow the efficient use of the optical energy returned from the eye.

[0049] FIG. 3a shows an example where a light beam from a light source 334 (e.g., a superluminescent diode or SLD) operating in a pulsed and / or burst mode is triggered through a light guide element 306 (e.g., a polarizing beam splitter (PBS)) into the patient's eye to form a relatively small spots on the retina to generate a wavefront that returns from the eye. The light guide element 306 must have a sufficiently large size of the interception of the light beam to ensure that an object beam that carries wavefront information from the eye within the desired measurement range of the optical power of the eye is completely intercepted without any disturbance at the edge of the light guide element.

[0050] The use of PBS can help suppress interference in the form of light reflected or scattered from other undesirable optical interfaces of the eye, such as the cornea and lens. The fact is that the relatively narrow SLD input light beam is linearly polarized in the first direction of polarization, and the light reflected or scattered from the cornea and lens is also, for the most part, linearly polarized in the first direction of polarization, while the light scattered on the retina has a large component polarized perpendicular to the first direction of polarization. Thus, PBS, as the light guide element 306, acts as both a polarizer for the SLD beam propagating to the eye and an analyzer designed to transmit only the object beam returned from the retina in the second orthogonal direction of polarization.

[0051] In addition to the need to filter out a component with a certain polarization, the wavefront leaving the eye also needs to be relayed to the image pickup plane of the wavefront. In FIG. 3a, this is achieved using the optical configuration of the 4-f wavefront repeater containing the first lens 304 and the second lens 316. In the plane B of the wavefront image, a matrix of partial wavefront selection elements, containing, for example, an annular matrix of partial wavefront selection apertures 318 and the corresponding annular matrix of lenses 320 focusing the partial wave front, in parallel selects and focuses a number of parts of the relayed wave front on the plane B of the image of the wave fr NTA. A corresponding matrix of position recording devices (PSDs) / detectors 322 (e.g., an annular matrix of lateral or quadrant detectors) is located behind the matrix of partial wavefront selection elements to detect the position of the centroid of the image spot of each selected partial wavefront.

[0052] In detail, to show partial wavefront selection elements and position recording devices (PSDs), in FIG. 3a, an enlarged view shows the optical elements of the wavefront selection and centroid detection cascades, the ring matrix of partial wavefront selection apertures 318 being deliberately separated from the ring matrix of partial wavefront focusing lenses 320, although in practice they are usually in contact or located in close proximity to each other . In an enlarged drawing, the PSD 322 ring array is positioned near the rear focal plane of the partial wavefront focusing lens 320 to provide a relatively sharply focused image spot on the PSD in the case of a plane wavefront, however, this is not always the case since the PSD 322 ring matrix before or after the focal plane of the lenses 320 focusing the partial wavefront. In an illustrative embodiment, due to the selection around the annular ring of the wave front from the eye, it is possible to determine a spherical and cylindrical refractive disorder of the eye and the axis of the cylinder. However, the pattern of elements for parallel selection of the partial wave front can take other forms, for example, the pattern of the spokes or the shape of a two-dimensional linear matrix.

[0053] FIG. 3a shows a synchronous amplifier 343 connected to receive output signals from a PSD matrix 322 for noise reduction. The display 345 may be connected to an electronic system 336 that receives the output of the synchronous amplifier 343. The operation of the synchronous amplifier 343 is described below with reference to FIG. 4. The electronic system 336 has processing capabilities for processing the output of the synchronous amplifier 343, including the use of algorithms to determine refraction, aberrations, and other diagnostic or clinical factors. The display 345 can be implemented as a current indicator associated with a surgical microscope, or a large-screen display or a rear projection display, or as part of a personal computer or workstation.

[0054] Note that, compared to conventional wavefront sensor systems, the illustrative embodiment described herein has a number of features that, in one combination or another, provide its advantage for refractive eye surgery. Firstly, the partial wavefront selection elements are physically separated from each other, due to which, their density is generally lower than the density of the standard elementary lens matrix used in a typical Shack-Hartman wavefront sensor. This is achieved by increasing the distance between the elementary lenses or the pitch of the elementary lenses or by increasing the diameter of each elementary lens compared to the diameter of the elementary lens used in a typical Shack-Hartman wavefront sensor. Alternatively, the focal length of the elementary lenses of the matrix of elementary lenses can be reduced compared to the focal lengths of the elementary lenses used in a typical Shack-Hartman wavefront sensor. As a result, it is possible to cover a sufficiently large range of measurement of optical power without mutual interference, i.e. the image spot of the selected partial wavefront getting on an inappropriate PSD.

[0055] To illustrate this, in FIG. 3b shows a matrix of elementary lenses of a typical Shack-Hartman wavefront sensor with a corresponding matrix of position recording devices / detectors and how the maximum range of optical power measurement without mutual interference is achieved. In the present description, the term “mutual interference" means a condition where the entire light beam or part of it to be focused by an elementary lens on a corresponding detector is focused on an adjacent detector.

[0056] The array of 342 elementary lenses of a typical Shack-Hartmann wavefront sensor is densely packed, that is, elementary lenses are placed next to each other without any gaps. In this case, a large number of elementary lenses per unit area, and the selection density for measuring the wavefront is high. Based on the fact that the wavefront to be measured is, as shown, a spherical converging wavefront 344, the maximum average slope of the partial wavefront, θ _m , which can be measured without interference, will be limited by the radius r and the focal length f of each elementary lens where θ _m = tan ^-1 [r / f]. FIG. 2 illustrates that the wavefront curvature increases for large positive or negative optical power values. Thus, θ _m indicates the maximum value of the measuring range of the optical power.

[0057] FIG. 3b it is shown that there is an angular distribution of the angle of inclination of the partial wavefront, and the partial wavefront selected by the leftmost elementary lens will be focused by this leftmost elementary lens to form a light spot that falls on the right boundary of PSD1 between PSD1 and PSD2. As you can see, any additional increase in the convergence or the absolute value of the optical power of the converging spherical wave front will cause the tilt angle to exceed θ _m and cause the light spot selected by the elementary leftmost lens to go beyond the boundary between PSD1 and PSD2 , in PSD2, thereby causing mutual interference. In fact, since the selected partial wavefront is convergent, the focused spot is actually in front of the focal plane 346, and accordingly, the corresponding image spot on the focal plane 346 will be wider than the image spot in sharp focus, so the measurement range of the slope of the partial wavefront is slightly smaller than θ _m . A similar situation exists for the elementary lens on the far right and two position recording devices / detectors PSD8 and PSD7.

[0058] On the other hand, if the wavefront is a spherical diverging wavefront, sharply focused image spots will generally be located behind the focal plane 346, so the light spot on the focal plane 346 will also be wider than the sharp focus image spot , and, accordingly, the measuring range of the slope of the partial wave front will again be slightly less than θ _m . If the wavefront is not spherical, but has a prismatic tilt and / or astigmatism and / or even other high-order aberrations, the local tilt of the partial wavefront selected by any of the elementary lenses may exceed the limiting tilt angle and the measurement range θ _m .

[0059] If the elements of the parallel partial wavefront selection are not densely packed, but reasonably distributed, with proper control of the center-to-center distance between the two elements, then mutual interference can be deliberately avoided and a certain desired sufficiently large measuring range of the optical power can be achieved.

[0060] FIG. 3c shows an illustrative embodiment of a configuration of partial wavefront sampling elements with a corresponding array of position recording devices / detectors, and illustrates that it is possible to increase the maximum optical power measurement range without interference. In the illustrated example, each partial wavefront selection element comprises an elementary lens 352 and an aperture 359 in front of the corresponding elementary lens. In other words, the masked aperture matrix mask 358 is combined with the corresponding array of elementary lenses 352 to act as a matrix of elements for parallel selection of the partial wavefront. Based on the fact that the focal length of each elementary lens is the same as shown in FIG. 3b, and is represented by the same f, whereas now the distance from the center of one elementary lens to the boundary or the midpoint between the two elements of the partial wavefront selection is d, as shown, the maximum average slope of the partial wavefront, which can be measured without mutual interference , now there will be β _m = tan ^-1 [d / f]. Since d is greater than r, the measurement range of the local slope of the partial wavefront thus increases. In fact, in FIG. 3c shows a more convergent spherical wavefront 354, which is selected than the wavefront shown in FIG. 3b, with the restriction imposed by the condition β _m = tan ^-1 [d / f]. Obviously, the absolute value of the optical power of the converging spherical wave front 354 shown in FIG. 3c, which can be selected without interference, is higher than that of the wavefront 344 shown in FIG. 3b.

[0061] FIG. 3c, the PSD widths are increased compared to the PSD width in FIG. 3b, i.e. d is greater than r. The use of wider PSDs instead of narrow PSDs with longer gaps between them makes it possible to ensure that with an increase in the slope of the partial wavefront, the light spot incident on the corresponding PSD can be captured by the corresponding PSD. Otherwise, if the PSD is the same smaller size as shown in FIG. 3b, but with diversity, an increase in the slope of the partial wavefront will cause the light spot of the partial wavefront to fall into the space between the photosensitive region of the PSD. In other words, the light spot will not be captured by the PSD to generate an electrical signal.

[0062] Furthermore, in FIG. 3c, the elementary lenses have an increased diameter compared to the diameter of the elementary lenses of FIG. 3b, but have the same focal length. The design of a larger elementary lens with the same focal length has the advantage that when combining such an elementary lens with a variable aperture, changing the size of the aperture can provide flexibility in controlling the size of the partial wavefront to be sampled in an increased range of selection size. For example, to measure refractive error, which involves only determining the values of the spherical and cylindrical optical forces and the axis of the cylinder, an increased sampling size of the partial wavefront can provide the advantage of averaging, as well as reducing the data processing load. In other words, the high spatial density of the wavefront sampling, which would normally be provided by a standard Shack-Hartman wavefront sensor, may be unnecessary for this type of refractive measurement and can significantly increase the time of capture, transfer and processing of data, thus slowing down the operation of the wavefront sensor and making it too slow for real-time refractive surgery applications.

[0063] On the other hand, if it is necessary to operate on only a small area of the cornea using, for example, the LASIK system, the size of the laser ablation spot on the cornea is generally much smaller than the size of a typical elementary lens of a Shack-Hartman wavefront sensor. In this case, the aperture shown in FIG. 3c, respectively, can be made sufficiently small, and scanning the wavefront, as will be discussed below, can be used to ensure registration of the non-averaged wavefront over a small area of the cornea so that very high measurement accuracy can be achieved with respect to measuring wavefront aberration high order. In fact, in some illustrative embodiments, the aperture matrix is activated in the sense that the size of the aperture can be actively controlled. It should be noted that the template matrix of apertures can also be placed after the template matrix of elementary lenses and may not be absolutely necessary, since their function can be served by the diameter of the elementary lens.

[0064] Furthermore, it follows from the formula for calculating θ _m that the measurement range of the slope of the partial wavefront without interference, θ _m , can also be increased by choosing a smaller focal length f. In this case, the size of each PSD can be reduced, while still providing a measuring range for the slope of the partial wavefront. However, the sensitivity of the slope measurement will also decrease, since for the same amount of change in the slope of the partial wavefront, the movement of the light spot on the PSD will be less, which is well known to specialists in this field of technology.

[0065] To provide even more flexibility, some illustrative embodiments use an elementary lens matrix having a variable focal length or an elementary lens matrix with specific subgroups of an elementary lens matrix having different focal lengths. A subset of elementary lenses with an increased focal length can provide better sensitivity, while a subgroup of elementary lenses with a reduced focal length can provide an increased dynamic range for measuring the slope of a partial wavefront. There may be two or three or more subgroups of elementary lenses and, accordingly, two or three or more sets of position detection detectors located at different distances from the elementary lenses.

[0066] A significant problem with existing wavefront sensors used in vision correction operations is that the detection of the wavefront returned from the eye is carried out in the presence of optical or electronic background noise. Examples of problematic background noise components are ambient light incident on the detector and 1 / f noise generated by the detector itself, and other emitted or conducted electronic noise. Both of these background noise components have significant amplitudes at the frame rate of standard two-dimensional image sensors based on CCD / CMOS.

[0067] In some illustrative embodiments, the light source used to create an object wavefront from the eye operates in a pulsed and / or burst mode. The pulse repetition rate or a frequency exceeding the typical frame rate of a standard two-dimensional CCD / CMOS image sensor. For example, the pulse frequency of the light source in this illustrative embodiment may be in the kilohertz range or higher. For an CCD / CMOS image sensor, the frame rate is usually from about 25 to about 30 frames per second. The PSDs of the present disclosure are two-dimensional position recording devices / detectors (PSDs) that all have a sufficiently high time-frequency response, which allows them to operate in synchronous detection mode synchronously with a pulsed light source at a frequency above the 1 / f noise frequency range. An electronic control and detection system is connected to at least the light source and the PSD matrix and is configured to synchronize the operation of the light source and parallel PSDs. The electronic control and detection system can also be connected to a matrix of variable partial wavefront sampling apertures to further control the size of the sampling aperture if sampling apertures are active.

[0068] FIG. 4 is a block diagram showing one illustrative embodiment of a synchronous detection amplifier 400. Note that phase-sensitive synchronous detection is a powerful synchronous detection method well known to those skilled in the art for detecting weak signals that can be masked by noise, which is much stronger than the signal of interest. The mixer 496 has a first input connected to the output of the preamplifier 495, the input of which receives an alternating signal from the PSD. The mixer 496 has a second input connected to the output of the phase synchronization circuit 497, which is synchronized with a reference signal that drives and clocks the SLD. The input signals are mixed (multiplied) by the mixer 496 to form the output signal of the mixer. The output of mixer 496 passes through a low-pass filter 498 and is amplified by output amplifier 499 to generate the output of synchronous detection amplifier 400.

[0069] Now we describe the operation of the synchronous detection amplifier. The signal from the PSD to the preamplifier 495 includes a component at a reference frequency that indicates the deviation of the partial wavefront measured by the position detection detector. The amplitude of this component is the desired output of the synchronous detection amplifier. The PSD input also includes noise signals at a low frequency, such as ambient light and 1 / f noise from the detector.

[0070] At the input of the phase synchronization circuit (PLL), a signal having a substantial amplitude only at the reference frequency is supplied.

[0071] The amplitudes of the signals supplied to the mixer are multiplied. Each frequency component of the amplified PSD signal is converted into a first output component of the mixer at a frequency equal to the sum of the frequency of the frequency component of the PSD and the reference frequency, and a second output component of the mixer at a frequency equal to the frequency difference between the frequency component of the PSD and the reference frequency.

[0072] A low-pass filter 498 passes signals having a frequency close to zero (constant signal) and blocks signals having frequencies markedly different from zero (variable signals). All noise components at frequencies other than the reference frequency are blocked, since the sum and difference of the frequencies of the noise and the reference signal are not equal to zero, therefore both output components of the mixer are variable signals and are blocked by a low-pass filter.

[0073] The frequency of the first mixer output for the frequency component of the PSD signal at the reference frequency is equal to the sum of the reference frequency with itself, which is twice the reference frequency and, thus, is an alternating signal that is blocked by the low-pass filter. However, the frequency of the second output signal of the mixer for the frequency component PSD at the reference frequency is equal to the difference between the reference frequency and itself, which is zero. This is a constant signal that is passed through a low-pass filter.

[0074] Accordingly, the output of the synchronous amplifier is a measure of only the frequency component of the PSD signal at the reference frequency. All noise signals at different frequencies are blocked by a low-pass filter. The signal passed through the low-pass filter can be further amplified by another amplifier 499 for further analog-to-digital (A / D) conversion along the signal path.

[0075] It should be noted that each PSD may have more than one photosensitive region (for example, 4, as in the case of a square detector), corresponding to more than one photodiode or photodetector. When implementing parallel synchronous detection, the required number of channels is equal to the number of parallel PSDs multiplied by the number of lines of the photodetection signal of each PSD. Due to the parallel sampling, it is possible to simultaneously collect a certain number of samples of the partial wave front along the wave front.

[0076] In FIG. 4, the A / D converter and other parts of the electronic detection and control module are not shown. Activating the A / D converter at the same frequency as the signal clocking the SLD can also allow the collection of both dark and light samples before and during the pulse of the SLD to further eliminate the effects of electromagnetic interference, as well as ambient light from the room or microscope, on which the device can be mounted.

[0077] Note that traditional wavefront sensors generally do not use a light source in a pulsed and / or burst mode (at least in the frequency range above the 1 / f noise region, that is, around and outside the kilohertz range), because either the light source for wavefront sensors used in astronomy, for example, a distant star in space, gets out of control (see, for example, US6784408), or there is no advantage to the light source operating in pulsed or burst mode, since a typical sensor images on Snov CCD / CMOS is not sufficiently high frame rates to operate in the frequency range above 1 / f noise.

[0078] The Hartman-Shack wavefront sensor can operate by selectively blocking some of the elementary lenses from the Hartman-Shack elementary lens array (see, for example, US7414712) to cover a wide range of optical power measurements. However, this approach is costly and, nevertheless, suffers from the same limitation that the image sensor used is scanned at a low frame rate.

[0079] Illustrative embodiments are described herein, where partial wavefront selection elements are preferably physically separated from each other in the wavefront image plane B, as shown in enlarged view in FIG. 3a. Note that in the illustrative embodiment shown in FIG. 3a, each partial wavefront selection element comprises an aperture and a focusing elementary lens. However, the focusing elementary lens can either be directly used as an aperture or even removed. In the latter case, the beam of the selected partial wavefront will not be focused, but will nevertheless fall as a light spot on the corresponding PSD with different centroid positions for different slopes of the partial wavefront, although, in general, the aperture size should be smaller than the size of the PSD to avoid mutual interference.

[0080] In order to separately show the matrix of partial wavefront selection apertures and the matrix of focusing lenses of the partial wavefront, in an enlarged drawing of FIG. 3a they are deliberately separated from each other. In practice, they are usually located in close proximity to each other. A large measuring range of the optical power is guaranteed by physically designing the spacing of the partial wavefront selection elements so that in the designed large optical power range, the slope of any selected partial wavefront will not be focused to fall on the adjacent PSD.

[0081] In the illustrative embodiments, a higher energy output can be achieved, although at the same time, 1 / f noise can be significantly reduced, which allows you to effectively filter out background noise of zero or low frequency, for example, noise generated by the light of a surgical microscope .

[0082] These features make the illustrative wavefront sensor described herein, when combined with or attached to an ophthalmic surgical microscope, highly suitable for surgery for correcting vision, such as cataract surgery. A cataract surgeon can perform an operation without stopping halfway to turn off the light of the surgical microscope and wait for the capture of multiple frames of data and process the data to obtain a refraction measurement.

[0083] According to these illustrative embodiments, the dynamic range of the measurement of optical power can be made large enough (for example, up to ± 30 diopters) to fully capture the refractive state of even the aphakic eye. In addition, by selecting only the correctly selected number of partial wave fronts around the annular wavefront ring from the patient’s eye, it is possible to obtain the values of the spherical and cylindrical optical forces, as well as the cylinder axis, which are necessary to select an intraocular lens (IOL) and to confirm, for example, emmetropia or the assigned value of the spherical optical power of the pseudophakic eye. By choosing the right number of wavefront samples around each ring matrix, you can significantly reduce the necessary data transfer speed and data processing resources.

[0084] We now describe illustrative embodiments that provide more spatial sampling points and / or higher spatial resolution than conventional ophthalmic wavefront sensors can normally provide, although this may not be absolutely necessary for cataract surgery. These embodiments may also measure higher order aberrations, and possibly also provide a two-dimensional wavefront map. These illustrative embodiments include a light beam angular scanning device 312 (e.g., an electro-optical or magneto-optical beam deflector) that can be placed in the Fourier transform plane 4-f of the repeater, as shown in FIG. 3a, for a transverse shift or scanning of the wavefront in the plane B of the wavefront image relative to the matrix of partial wavefront selection elements. Thus, it is possible to achieve sub-aperture spatial resolution, which is disclosed in US 6376819, and also to select these parts of the relayed wavefront between the sampling apertures, if the relayed wavefront, in contrast, is static.

[0085] FIG. 5 shows one example of sequential transverse shear or wavefront scanning in relation to the optical configuration shown in FIG. 3a. In this example, 8 elementary partial wavefront selection lenses 501 are arranged in the form of an annular matrix in the wavefront image plane B with sufficient spacing between any two adjacent elementary lenses so that there is no mutual interference within the designated measuring range of refractive optical power. The relayed wavefront is shown as a circular disk 502, with 8 elementary lenses 501 taking 8 parts of the relayed wavefront. In the absence of any shift or scanning of the wavefront, 8 selected partial wavefronts have rotational symmetry with respect to the wavefront image 502.

[0086] Circles 502-520 represent the first portion of the relayed wavefront that falls onto an array of elementary lenses. The location of the circle, i.e. the first part of the wavefront, is scanned in different positions, as shown in various drawings, which allow selection in a subpart of the first part.

[0087] Of the 4 rows shown on the right side of FIG. 5, the two upper rows (503-510) show one example of the effect of a sequential transverse shift of a relayed wavefront with respect to 8 elementary lenses. Circles 503-510 demonstrate that the relayed wavefront is sequentially shifted by the same distance, respectively, in the directions to the right, right and down, down, down and left, left, left and up, up and up and right.

[0088] The two lower rows (513-520) show the equivalent result of moving the matrix of elementary lenses relative to the wavefront instead of moving the wavefront relative to the matrix of elementary lenses. 8 circles made by a dashed line, in each case from 513 to 520, show the initial position of the selection of 8 elementary lenses relative to the unshifted first part of the relayed wavefront. 8 circles made by a solid line, from 513 to 520, demonstrate the equivalent relative displacement of 8 elementary lenses relative to the initial positions of the elementary lens, if the first part of the relayed wavefront is considered to be stationary. The full selection template 512, due to the shift depicted in the upper two rows, shows the accumulated selection effect.

[0089] From the full selection template 512, it can be seen that in the absence of a wavefront shift, only 8 source sub-parts of the wavefront ring matrix will be selected, and that in the presence of a wavefront shift, other wavefront sub-parts can be selected.

[0090] In the illustrated example, overlapping selections are shown, as can be seen in the full selection template 512. This indicates that spatial resolution of the selection can be achieved, which is smaller than the size of the selection aperture (which in this illustrated example is equal to the diameter of an elementary lens). In fact, you can control the scanning angle of the scanner 312 to achieve any desired spatial resolution of the selection, provided that the beam scanner can be controlled with any desired practical achievable angular accuracy. In addition, the full selection template 512 also demonstrates that as a result of the transverse shift of the relayed wavefront, it is possible to select not only parts of the unshifted wavefront between any two adjacent elementary lenses, but also parts of the wavefront to the center and from the center of the unshifted wavefront. In the full selection template 512, one can already see that, if necessary, three ring rings can be selected. Any part of the wavefront can be selected by controlling the beam shifter 312.

[0091] It should be noted that the matrix of partial wavefront selection elements is not required to have the shape of an annular matrix, as shown in FIG. 3a. For example, it can be in the form of a rectangular matrix, provided that its elements are sufficiently physically separated from each other to ensure coverage of a sufficiently large dynamic range for measuring the violation of refractive power without mutual interference. Alternatively, they can be arranged more densely, provided that the focal length of the elementary lens behind each partial wavefront selection aperture is correspondingly smaller, and that the distance between the elementary lenses and PSD is correspondingly reduced. It should also be noted that the number of elementary lenses is not required to be limited to 8, and that they can be placed in any form and in any quantity.

[0092] As discussed above, comparing the configurations shown in FIG. 1 and FIG. 2, if scanning is performed using a 4-f repeater, then the beam scanner 312 needs to have a large beam interception window size. In order to overcome this limitation and also provide various other improvements, FIG. 6 shows another illustrative embodiment. As can be seen from FIG. 6, the optical configuration, in some aspects, is similar to that shown in FIG. 2. However, there are a number of new features that can be implemented either individually or in conjunction with others.

[0093] In the illustrative embodiment shown in FIG. 6, a relatively narrow beam of light from a light source 634 (e.g., a superluminescent diode (SLD)) operating in a pulsed and / or burst mode is triggered through an adjustable focus lens 637 and is guided by a light guide member 606 (e.g., a polarizing beam splitter or PBS) to patient's eye to generate a wavefront returned from the eye. A change in focus from lens 637 can be used to ensure that the spot size of the light beam when it hits the retina is relatively small for various refractive conditions of the eye. In addition, the scanning mirror 680 for scanning the SLD beam can be placed in the back focus of the first lens 604 so that the SLD beam scanner is located in the position associated with the position of the retina of the emmetropic eye. Thus, the SLD beam angular scan device 680 will cause a transverse scanning of the SLD beam relative to the plane of the cornea, while allowing the SLD beam to fall into the same spot on the retina if the eye is emmetropic. This scanner can be used to scan the beam of SLD to accompany any movement of the eye, so that the beam of SLD can always enter the eye from the same place in the cornea.

[0094] Instead of using a 4-f wavefront repeater, as shown in FIG. 3a, a wavefront relay system 8-f comprising a first lens 604, a second lens 616, a third lens 640, and a fourth lens 642 is used to relay the wavefront from the pupil or cornea plane through the intermediate wavefront image plane B to the final wavelength image acquisition plane front D. Such an 8-f wavefront repeater can be considered as containing two cascade-connected 4-f repeaters. The first repeater includes first and second lenses that direct the wavefront relay beam through the Fourier transform plane A to the intermediate wavefront image plane B. The second repeater includes a third and fourth lens, which further relay the wavefront from the intermediate wavefront image plane B through the Fourier transform plane C to the final wavefront image plane D. The advantage of such an optical configuration of the 8-f wavefront repeater has been discussed with reference to FIG. 2, and further details can be found in the patent application US20120026466 belonging to the same applicant.

[0095] Instead of using only one partial wavefront selection element and one PSD, as shown in FIG. 2, a matrix of partial wavefront selection elements, comprising, for example, a rectangular matrix of 618 apertures and a corresponding rectangular matrix of 620 elementary focusing lenses of a partial wavefront, can be located essentially in the image plane D of the final wavefront to select and focus the desired partial wavefront matrix fronts. Again, the partial wavefront selection elements can be physically separated from each other and / or the focal length of the matrix of elementary lenses can be appropriately selected so that a large measurement range of the refractive power disturbance can be covered without interference.

[0096] These elements can be combined with an appropriate matrix of parallel PSDs to detect the centroid position of the image spot of the selected partial wavefront matrix and to achieve parallel wavefront selection with synchronous detection by synchronizing the detectors with a pulsed light source.

[0097] As an alternative to directly placing the PSD substantially on the rear focal plane of the elementary lenses behind the partial wavefront selection elements, the lens 621 can be used for relaying and also preferably optical magnification of the imaginary image spots formed on the imaginary image spot plane 622a as shown in enlarged view in FIG. 6 into a new plane of valid PSD 622, which is well known to those skilled in the art (see, for example, US6595642).

[0098] This lens 621 is particularly useful if a relatively high density array of elementary lenses with a reduced focal length is used to cover the desired large range of optical power. Usually, such a matrix of elementary lenses has a relatively small step, i.e. the spacing between the centers of the elementary lenses in this matrix is, for example, from 0.5 mm to 1.0 mm, while each PSD can be relatively large (for example, in the case of a square detector, about 5 mm in diameter). Thus, in order to achieve a one-to-one correspondence, the spots of the image formed by the matrix of elementary lenses can be optically enlarged and relayed using the lens 621 to the matrix with an increased step to increase the distance between two adjacent PSDs so that the PSDs can physically fit on the substrate.

[0099] As in the case of FIG. 2, a compact scanner or beam deflector 612 may be located on the second Fourier transform plane C to fully intercept and angularly scan the entire object beam that carries wavefront information of the eye over a desired large range of refractive error. However, compared to FIG. 2, the required range of angular scanning or beam deflection can now be significantly reduced. The fact is that, due to the use of a matrix of partial wavefront selection elements, the object beam needs to be scanned only in such an angular range in which the transverse shift of the wavefront in the image plane D of the final wavefront is equal to the step, i.e. the distance between the centers of neighboring PSDs in the matrix of partial wavefront selection elements in the x and y directions. Thus, the selection can be carried out in all parts of the wavefront incident between any two elements of the selection of the partial wavefront, if the relayed wavefront is not otherwise scanned. This allows the use of beam scanners of various types in addition to a reflective scanner based on MEMS, for example, a transmission electro-optical or electromagnetic scanner, which, in general, can cover only a relatively small angular scanning range.

[00100] By analogy with the case shown in FIG. 3a, a synchronous amplifier 643 may be connected to receive output signals from a PSD 622 matrix for noise reduction. The display 645 may be coupled to an electronic system 636 that receives the output of the synchronous amplifier 643. The electronic system 636 has processing capabilities to process the output of the synchronous amplifier 643, including the use of algorithms to determine refraction, aberrations, and other diagnostic or clinical factors. Display 645 can be implemented as a current indicator associated with a surgical microscope, or a large-screen display or a rear projection display, or as part of a personal computer or workstation.

[00101] In FIG. 7 shows one example of a successive lateral shear or wavefront scan for the optical configuration shown in FIG. 6. In this example, 21 elementary partial wavefront selection lenses 701 are placed in a two-dimensional linear matrix format in the wavefront image plane D with sufficient spacing between any two adjacent elementary lenses so that there is no mutual interference within the designated measurement range of the refractive error optical power. As in FIG. 5, the first part of the relayed wavefront is shown in the form of a circular disk 702 incident on an array of elementary lenses, with 21 elementary lenses 701 selecting 21 sub-parts of the first part of the relayed wavefront. In the absence of any shift or scanning of the wavefront, 21 the selected sub-part of the first part of the relayed wavefronts is regularly distributed in a two-dimensional matrix format relative to the relayed wavefront 702.

[00102] Of the 4 rows shown in FIG. 7, the two upper rows (703-710) show one example of what happens when a relay wavefront sequentially undergoes a transverse shift relative to 21 elementary lenses. Circles 703-710 show that the first part of the relayed wavefront is sequentially shifted by the same distance in the horizontal and / or vertical direction, respectively, in the directions to the right, right and down, down, down and left, left, left and up, up and up and to the right.

[00103] The two lower rows (713-720) show the equivalent result of moving the matrix of elementary lenses relative to the wavefront instead of moving the wavefront relative to the matrix of elementary lenses. 21 circles made by a dotted line placed in the format of a two-dimensional linear matrix in each case from 713 to 720 demonstrate the initial position of the selection of 21 elementary lenses relative to the unshifted first part of the relayed wavefront. In circles 713-720, 21, a solid line circle shows an equivalent relative displacement of 21 elementary lenses relative to the initial positions of the elementary lens when the first part of the relayed wavefront is considered to be stationary. The full selection template 712 shows the cumulative selection effect. From the full selection template 712, it can be seen that in the absence of a wavefront shift, 21 initial parts of the elementary relay of the relayed wavefront will be selected, and in the presence of a wavefront shift, regions around 21 of the initial elementary lens can be selected.

[00104] In fact, in the illustrated example, a lateral and / or vertical lateral shift is shown by a distance equal to the diameter of each elementary lens, and an initial pitch or spacing between two horizontal or vertical elementary lenses is set to (o) three times the diameter of each elementary lens. In other words, the gap width is twice the diameter of each elementary lens. As a result, the illustrated scan allows the selection of a relayed wavefront, as if the wavefront was selected by a densely packed two-dimensional linear matrix of elementary lenses, as in the case of a typical Hartmann-Shack wavefront sensor.

[00105] It should be noted that it is possible to control the scanning angle of the beam scanner 612 and the pulsation of the SLD to realize sampling at smaller transverse shear wavefront distances and, therefore, to achieve any desired spatial resolution of the sampling. In addition, the illustrated example also demonstrates that by using a two-dimensional linear matrix of partial wavefront selection elements, the beam scanner 612 only needs to scan a small angular range in the horizontal and vertical directions so that all parts of the relayed wavefront can be selected.

[00106] Note that the wavefront selection aperture matrix and / or PSD can also be activated. The aperture size for selecting partial wave fronts can be dynamically adjusted using, for example, variable-aperture arrays or variable-aperture arrays on a liquid crystal basis. Apertures can also be active in the sense that different portions of the relay wavefront image can be directed to different PSDs using the MEMS mirror array, as disclosed in US6880933. The focal length of the partial wavefront focusing lens can also be changed using, for example, liquid crystal microlens and liquid lens arrays based on a flexible membrane. In addition, the position of the PSD or the position of the matrix of elementary lenses for focusing the partial wavefront can also move in the longitudinal direction.

[00107] In the illustrative embodiments presented in FIG. 3a and FIG. 6, an electronic system is provided connected to at least the light source and the PSD to synchronize the operation of the light source and the PSD at a frequency above the noise frequency range 1 / f so that substantially zero or low frequency background noise can be filtered out. . In addition, the electronic system can also be connected to a variable focus lens 637 for controlling SLD beam focusing, to an SLD beam scanner 680, to an object wavefront scanner / deflector 612, to aperture matrix 618, to elementary lens matrix 620, and to a lens 621. These electronic connections are used to control the operation of connected elements or devices.

[00108] Furthermore, although according to FIG. 3a and 6, the SLD beam is launched behind the first lens, the SLD beam can be launched from anywhere between the eye and the image plane D of the final wavefront (for example, in front of the first lens or even behind the second lens), and its divergence or convergence can also be adjusted by others by means other than a variable focus lens 637 (for example, using an axially movable lens) to ensure that the desired light spot is formed on the retina of different eyes.

[00109] Under the pulsation of a light source should be understood any kind of temporary modulation of the light source. For example, an SLD can be modulated between on / off states or dark / bright states; it can also be modulated between the state of the first light level and the state of the second light level; SLD can also be modulated according to a sinusoidal law. According to another example, the light source operates in batch mode to create a stream of light pulses, in which each pulse is also modulated by the carrier frequency or modulation frequency. Accordingly, by synchronous detection or synchronized detection should be understood any means of synchronous or coherent detection. Synchronous detection can be carried out at a high carrier frequency and / or at a pulse repetition rate.

[00110] The optical path for triggering the SLD beam and also for guiding the returning object beam can be folded in one way or another to save space in order to make the wavefront sensor module compact. This means that mirrors or other folding elements of the optical beam can be used to fold the various optical paths. The beam scanner may be transmissive or reflective. In addition to the wavefront repeater in a 1: 1 ratio, there may be an optical increase or decrease in the wavefront from the eye to the image plane of the intermediate wavefront and to the image acquisition plane of the final wavefront. This means that the focal length of all the lenses used to relay the wavefront can have different values. In addition to two cascaded 4-f wavefront transponders, there may be more cascaded 4-f or other wavefront transponders.

[00111] Due to the fact that the B plane of the intermediate wavefront image shown in FIG. 6, is coupled to the plane of the object wavefront and the image plane D of the final wavefront, the compensator or the wavefront defocus shift element 689 can be located on plane B and controlled by the electronic system. Thus, the wavefront sensor system can be converted into an adaptive optical system for various other applications. In addition to simply completely compensating for the total wavefront aberration, which is usually done for an adaptive optical system, it is also possible to partially or completely compensate for only one or more of the wavefront aberrations, so that the remaining uncorrected wavefront aberrations can manifest themselves more expressively and, therefore, they can It was more accurate to measure. For example, the degree of spherical defocusing may return to the compensator or bias element 689, which affects the divergence or convergence of the detected wavefront. This feedback can change the measured defocus in such a way that a closed-loop system is formed, and closed-loop control methods can be used to reduce the divergence or convergence of the measured wavefront to any desired value, most likely to bring it to a value close to zero, thus so that the wavefront is essentially flat. In addition, information about the sign and degree of defocus can be used to adjust the variable focus lens 637, which affects only the divergence or convergence of the SLD beam, to form an open-loop control system.

[00112] The spatial configuration of the partial wavefront selection elements and corresponding PSDs need not be placed at a regular constant pitch or in the format of a ring matrix or rectangular matrix, but can be in any format. For example, there may be two or more matrices in the form of an annular ring, where the elements of the partial wavefront selection of the outer annular matrix are spaced farther than in the inner (s) annular matrix (s).

[00113] In addition, the transverse position of the PSD can also actively change in accordance with the refractive condition of the patient’s eye. For example, in the case of an aphakic eye, the wavefront from the eye on the plane of the cornea is generally relatively divergent, and this wavefront, being relayed to the image plane of the final wavefront, will also be very divergent. In this case, if the matrix of the partial wavefront selection elements in the form of an annular ring is used to select the relayed wavefront, the corresponding ring PSD matrix can be moved radially outward relative to the matrix of the partial wavefront selection elements in the form of an annular ring so that if the relayed the wavefront is the ideal spherically diverging wavefront, the centroid of the image or light spot of each selected partial wave The front is located in the center or near the center of each respective PSD. Thus, any additional deviation of the wavefront slope from the imaginary ideal spherically diverging wavefront can be detected with high accuracy, since only the central part of each PSD is used to detect the centroid. In addition, it should be noted that the matrix of 320 or 620 elementary lenses (Figs. 3a and 6) may not be absolutely necessary, as in the case of the Hartmann-Shack wavefront sensor, in contrast to the Hartman wavefront sensor, since the Hartman hole matrix will also work .

[00114] In addition, the spatial light modulator (SLM) can also be combined with a matrix of high density elementary lenses, and SLM can work synchronously with the light source and also with the PSD matrix so that only a selected number of apertures open over a selected number of elementary lenses during the period of operation of the light source. For example, one or more ring matrices of elementary lenses can be opened, and the decision which ring matrix to open can be made depending on the value of the spherical or defocusing optical power of the object wavefront. Accordingly, the desired ring matrix of sample wavefront data will be collected. Selecting around only one annular matrix will give only refractive errors, but not high order aberrations, which will be enough for cataract surgery applications. Thanks to sequential scanning or opening of various elementary lenses, it is possible to measure aberrations of high orders.

[00115] In addition to lateral-action position detectors and quadrant detectors / sensors, other types of PSDs can be used that operate at a sufficiently high frequency and determine the centroid position of the image spot of the selected partial wavefront. For example, each PSD may be a cluster of 3 or more photodiodes. Each PSD of the PSD matrix can also be a few clustered pixels of a high-speed two-dimensional image sensor that has a high frame rate, although such an image sensor is likely to be expensive. Each PSD of a PSD matrix can also be a CMOS-based image sensor programmed to output only data from a certain number of pixels of a programmed area of interest (ROI) when the shutter is in global exposure mode. Currently, a traditional image sensor with a large number of pixels, in general, can be programmed to output data from only one ROI. However, this does not mean that in the future it will not be possible to simultaneously output multiple ROI data at sufficiently high frame rates with global exposure control. When this opportunity becomes a reality, it will be possible to directly use a single two-dimensional image sensor to extract the corresponding ROI matrix, as if it were a PSD matrix operating in the synchronous detection mode with a sufficiently high time-frequency characteristic. Pulse on time can be synchronized with camera exposure. In other words, the light source can be turned on for a short time while the camera collects the light. Alternatively, the SLD source can be turned on for a slightly longer time than the camera exposure time so that the effective pulse duration is determined by the camera exposure time.

[00116] In addition to standard synchronous detection, double sampling can also be used to further reduce noise. For example, a light source can be modulated between a bright state and a dark state. The PSD matrix can record the signal of the spots of the image formed by focusing the partial wavefronts in the bright state and also record the background signal in the dark state. When the background signal is subtracted from the signal recorded in the bright state, an improved estimate of the desired centroid of the image spots is obtained. In one example, a cluster or several clusters of pixel sensors of the CCD / CMOS image sensor can be programmed as one or more areas of interest (ROI) acting as a PSD matrix, and each ROI can be further divided into substrings and bright state substrings and substrings and pillars of a dark state. Each second (second) substring and column can be selected in every second bright and dark period. Thus, bright and dark selection can be achieved using the same ROI or PSD at a higher frame rate, since fewer pixels are used for each frame. One half of the pixels in each ROI can be synchronized with the “turn on” the light of the SLD, and the other half can be synchronized with the pulse of “turn off” the light of the SLD.

[00117] Alternatively, the electronic signal from the PSD matrix can be sampled at a frequency ten or more times the ripple frequency of the light source, converted to a digital signal, and then filtered by digital means. After converting to a digital signal, other digital signal extraction algorithms, such as Kalman filtering, can also be applied.

[00118] Furthermore, in addition to the traditional 4-f or 8-f wavefront repeater configuration shown in FIG. 3a and 6, any optical wavefront repeater configuration, for example, disclosed in US20100208203, can be used.

[00119] Other functions may also be added to the described illustrative embodiments. In FIG. 8 illustrates an embodiment in which a dichroic or long-wavelength transmitting beam splitter 860 is used to reflect at least a portion of the light to form a common image of the eye and to fix the eye, and to substantially transmit the near infrared light of the SLD to record the wavefront . A dichroic or long-wavelength transmitting beam splitter 860 must have a sufficiently large light interception window to ensure that the wavefront from the eye, within the desired measurement range of the optical power of the eye, is completely intercepted without disturbance at the edge of the beam splitter window.

[00120] The reflection of a dichroic or long wavelength transmitting beam splitter can perform two functions. The first is the direction of light in the visible or near infrared region of the spectrum returned from the eye to the image sensor 862 so that the on-line image of the pupil of the eye can be processed and displayed for various purposes, for example, to help the clinician align the eye with respect to the wavefront sensor. The source of light returned from the eye is a light source of light used, for example, in a surgical microscope, external light in a room, or light emitted directly from a wavefront sensor module. The second function is to direct the image of the visible fixation target 864 to the patient’s eye so that the eye can have a target on which to fix, if such fixation is necessary.

[00121] In addition, a small beam splitter 866 is installed along this path of the reflected light beam, which divides / combines the light beam of the fixation target and the light beam of the image sensor. This small beam splitter 866 may have various spectral properties. For example, it can be a simple 50:50 broadband beam splitter designed to operate in the visible and / or near infrared spectral range. If the fixation light source 864 has a relatively narrow spectrum, then to increase the optical efficiency, the reflection spectrum of this small beam splitter 866 can be matched with the spectrum of the fixation source to ensure good reflection of the fixation light and to transmit the rest of the spectrum to the image sensor 862.

[00122] The lens 868 in front of the image sensor 862 may be designed to provide the desired optical magnification of the live image of the front of the iris or pupil of the patient’s eye on the display. It can also be a dynamic lens, used, if necessary, to adjust the focal length to ensure that the plane of the image sensor is aligned with the plane of the pupil of the eye, which allows you to get a clear image of the pupil of the eye. It can also be a zoom lens, which allows the clinician / surgeon to use it to focus on either the cornea or the retina and, if desired, to change the magnification. Here you can also apply digital zoom.

[00123] The lens 870 in front of the fixation target 864 may be designed to provide the patient with a comfortable fixation goal of the desired size and brightness. It can also be used to adjust the focal length to ensure that the fixation target is paired with the retina, or to fix the eye at different distances, or even to blur the eye, if necessary for the clinician / surgeon. A fixation light source 864 may flash or blink or change colors at a frequency necessary to distinguish it, for example, from surgical microscope illumination light. The fixation target 864 may be an image, for example, a balloon illuminated from behind by a light source, or a microdisplay that can display the desired patterns, including dot arrays, under the guidance of a clinician / surgeon. In addition, the fixation target based on the microdisplay can also be used to instruct the patient to look in different directions so that an aberration map of the eye can be generated in the form of a 2D matrix that can be used to evaluate the visual activity of the patient’s off-center or peripheral vision.

[00124] The fixation target, image of the front of the eye, and / or other information can also be transmitted back to the microscope and observed through eyepieces (not shown). This information will be projected coaxially with the observer's observation line through a dichroic or beam splitter through a series of lenses or a physical distance that will be coplanar to the working distance of the microscope or slit lamps.

[00125] The image sensor 862 may be a black-and-white or color CMOS / CCD image sensor, and the fixation light source may be a red or green or other light emitting diode (LED), the output optical power of which is dynamically and / or manually controlled , based on different background lighting conditions. For example, when a relatively strong beam of light from a surgical microscope is turned on, the brightness of the fixation light source can be increased to make it easier for the patient to find the fixation target and focus on it.

[00126] In addition to providing a live image of the pupil of the eye, the image sensor signal can also be used for other purposes. For example, a live image may be displayed on a current reading indicator or displayed on a translucent microdisplay embedded in the eyepiece of a surgical microscope.

[00127] The live image can be used to detect the size and lateral position of the pupil of the eye. When it is determined that the pupil size is small and / or has moved relative to the wavefront sensor, a mechanism for selecting and / or selecting and / or shifting the wavefront can be started using information from the image sensor to select only the wavefront region centered on the patient’s pupil. In other words, pupil size and location information can be used in closed-loop mode to automatically and / or dynamically adjust and / or scale the wavefront selection. Thus, the active wavefront sampling apertures and / or the scanner can implement tracking of the direction of view. This ability to continuously monitor the pupil using internal adjustments and without moving the wavefront sensor and / or surgical microscope to which the wavefront sensor is connected or otherwise interferes with its use, allows the patient to continuously measure the wavefront violation of the patient through a surgical operation.

[00128] The wavefront sensor itself can also provide information for tracking the pupil, since the light intensity in the selected wavefront falls on the edge of the patient’s pupil, i.e. where the iris begins to block the light returning from the retina. Thus, the intensity detected by the wavefront sensor can provide a map of the patient’s pupil, which can be used to more accurately center the selection of the wavefront on the patient’s pupil.

[00129] In addition, pupil position information obtained from either an image sensor or a wavefront sensor can be used to provide a feedback signal for driving a scanning mirror 880 to provide an SLD beam to accompany eye movement so that the beam SLD always entered the cornea from the same designated location of the cornea, so that, for example, the specularly reflected SLD bundle returned by the cornea does not fall on the PSD of the wavefront sensor. The SLD beam can also be imaged by an image sensor to center the eye or to intentionally displace the SLD beam from the center of the pupil or to provide feedback / guidance to determine the position of the eye relative to the SLD beam. The object beam scanner 812 can also be adjusted by setting the correct offset to accompany the movement of the pupil of the eye.

[00130] Furthermore, when it is determined that the optical path obstructions are present, for example, when the eye is rinsed with water, or optical vesicles, or the eyelid, facial skin, surgeon's hand or surgical instrument or instrument are in the field of view of the image sensor and blocks the path of the wavefront relay beam, then the wavefront data can be discarded to exclude “dark” or “bright” data and at the same time the SLD 834 can be turned off.

[00131] In some illustrative embodiments, the result of the qualitative and / or quantitative measurement of the wavefront can be superimposed on the display of the live image of the pupil of the eye captured by the image sensor 862. In addition, the wavefront measurement result superimposed on the operative image of the pupil of the eye can be updated with such a frequency that there is a small delay between any change in the refractive state and the report on the change in refractive state provided by the wavefront sensor. This update can be achieved by averaging the detected wavefront data over the desired period and updating the result of the qualitative and / or quantitative measurement superimposed on the operative image of the eye with the desired refresh rate preferred by the surgeon.

[00132] It should be noted that the image sensor may be individually integrated in the configuration shown in FIG. 3a or FIG. 6 to work regardless of the purpose of fixation. In this case, the fixing target can also be individually integrated into the configuration shown in FIG. 3a or FIG. 6 to operate independently of the image sensor.

[00133] It should also be noted that the wavefront sensor of the illustrative embodiments can be combined with various ophthalmic devices for measuring the wavefront of the eye. In FIG. 9 shows one example of its integration with a surgical microscope 910, which allows you to observe the patient’s eyes, while continuously measuring the wavefront of the eye. In this integration, a beam splitter 915 is inserted along the observation line 903, from the microscope user's eye to the patient’s eye, to create a second optical path linking the wavefront measurement system 900 and the patient’s eyes 938. Preferably, the beam splitter 915 is a dichroic beam splitter reflecting near infrared light, while transmitting the main part of the visible spectrum to the microscope user.

[00134] Due to this configuration, the wavefront measurement system 900 can emit light, preferably near infrared light, to the patient's retina 938, with a portion of the scattered light returning from the retina to the wavefront sensor. The scattering point on the retina returns some light, with a wavefront 901, which is relayed to the plane of selection of the wavefront of the wavefront measurement system 900, and its deviations from the plane or from the internally distorted wavefront of the wavefront sensor module, in the presence of internal wavefront aberration, indicate aberrations or refractions of the patient’s eye.

[00135] In FIG. 10 shows the integration of the wavefront sensor disclosed herein with a slit lamp. Again, a beam splitter 1015 can be inserted along the observation line 1003 from the user's slit lamp to the patient’s eye to create a second optical path connecting the wavefront measurement system 1000 and the patient’s eyes 1038. Note that the same wavefront sensor design can be used in every application, although a different design with a different working distance and corresponding changes is also possible depending on the requirements of a particular ophthalmic device.

[00136] In practice, it is preferable to use the same wavefront sensor design both with a slit lamp for examining a patient before and after surgery, and with a surgical microscope during a refractive operation. As used herein, the term 'ophthalmic device' refers to any type of ophthalmic microscope and / or other ophthalmic device, such as a fundus camera. Preferably, the wavefront sensor should not require special alignment or focusing of the microscope or other interference with the normal use of an ophthalmic device.

[00137] In addition, illustrative embodiments of the wavefront sensor can also be combined with a femtosecond laser or excimer laser, which is used for LASIK or cracking of the natural lens and corneal dissection / cutting. The operative image of the eye and the wavefront signal can be combined to indicate whether optical bubble (s) or other optical heterogeneity is / is present in the eye or anterior chamber before, during, or after a surgical operation on the eye. Wavefront information can also be used to directly control the LASIK in closed loop mode.

[00138] These embodiments may also be deployed to measure optics, eyeglasses or glasses, IOLs and / or control cutting / machining devices that create optics.

[00139] These embodiments can also be adapted to microscopes for cell and / or molecular analysis or other metrological applications. Illustrative embodiments can also be used for the manual manufacture of lenses, prescription glasses, microbiological applications, etc.

[00140] Although various illustrative embodiments that rely on the principles of the present invention are shown and described in detail here, those skilled in the art can readily derive various other embodiments also meeting these principles.

Claims (24)

1. Ophthalmic wavefront sensor containing:
a light source configured to generate a beam of light formed by pulses of light at a reference frequency in response to a reference signal oscillating / pulsating at a reference frequency;
a first light guide member configured to start the light beam from the light source into the patient’s eye, while the part of the light beam returning from the patient’s eye forms a wavefront reflected from the eye in the form of light pulses at a reference frequency;
the first wavefront optical relay system configured to relay the wavefront reflected from the eye from the first object plane of the first wavefront optical relay system located on the front of the patient’s eye to the first wavefront image plane of the first wavefront optical relay system along the first path of the beam, which can direct the relay beam of the incident wave front on the first object plane to the first image plane in new front;
an array of two-dimensional position recording devices, wherein each two-dimensional position recording device is configured to detect a two-dimensional deviation of the centroid of the image spot from the reference position and output a measurement signal indicating a two-dimensional deviation; and
a matrix of partial wavefront selection elements located upstream of the matrix of two-dimensional position recording devices, each selection element in the matrix of partial wavefront selection elements is configured to select the partial wavefront of the relayed wavefront and focus the selected partial wavefront on the corresponding two-dimensional position recording device in the matrix two-dimensional position recording devices, the elements of the partial wavefront selection physically ki spaced from each other so that each selected partial wavefront of the wavefront reflected from the eye focuses only on the corresponding two-dimensional position registration device corresponding to selection of a partial element of the wavefront. 2. The ophthalmic wavefront sensor according to claim 1, wherein the first optical wavefront relay system includes a first and second lens, each lens having a diameter, a focal length and an optical axis, focal lengths and diameters of the first and second lenses are selected for direction a wavefront relay beam on the first object plane, to the first wavefront image plane. 3. The ophthalmic wavefront sensor according to claim 2, wherein the first optical wavefront relay system is configured to relay the wavefront reflected from the eye from the first object plane located on the front of the patient’s eye to the first Fourier transform plane located between the first and second lenses, and in the first plane of the wavefront image along the first path of the beam. 4. The ophthalmic wavefront sensor according to claim 3, further comprising a first beam scanner located in the first Fourier transform plane located between the first and second lenses and configured to shift the relayed wavefront relative to the matrix of partial wavefront selection elements, wherein the matrix of elements partial wavefront selection is essentially in the first plane of the wavefront image. 5. Ophthalmic wavefront sensor according to any one of paragraphs. 1-4, and the reference frequency of the light source above the frequency range 1 / f noise. 6. The ophthalmic wavefront sensor according to claim 1, further comprising:
a second wavefront optical relay system having a second object plane located essentially on the first wavefront image plane, configured to further relay the wavefront reflected from the eye from the second object plane to the second wavefront image plane along the second beam path which can direct the incident beam relay beam on the first object plane to the second image plane of the wave front; moreover, the matrix of elements for the selection of the partial wave front is located essentially on the second plane of the image of the wave front. 7. The ophthalmic wavefront sensor according to claim 6, wherein the first optical wavefront relay system includes a first and a second lens, each lens having a diameter, a focal length and an optical axis, focal lengths and diameters of the first and second lenses are selected for direction a wavefront relay beam on a first object plane to a first image plane of a first wavefront; and
the second optical wavefront relay system includes a third and fourth lenses, each lens having a diameter, focal length and optical axis, focal lengths and diameters of the third and fourth lenses are selected for further direction of the incident wave relay relay beam on the first object plane to the second image plane of the wavefront. 8. The ophthalmic wavefront sensor according to claim 7, wherein the third lens is configured to direct the wavefront reflected from the eye to a second Fourier transform plane located between the third and fourth lenses. 9. The ophthalmic wavefront sensor according to claim 8, further comprising a first beam scanner located in the second Fourier transform plane between the third and fourth lenses, configured to shift the relayed wavefront relative to the matrix of partial wavefront selection elements. 10. The ophthalmic wavefront sensor according to claim 4 or 9, wherein the first beam scanner is configured to track the eye so that the eye is always selected only in the desired part (s) of the wavefront, even when the eye moves. 11. The ophthalmic wavefront sensor according to claim 4 or 9, further comprising a second beam scanner configured to track the eye by directing the light beam to generate a wavefront reflected from the eye to accompany the eye. 12. The ophthalmic wavefront sensor according to claim 11, wherein the second beam scanner is located on the rear focal plane of the first lens of the first optical wavefront relay system. 13. The ophthalmic wavefront sensor according to claim 1, further comprising a wavefront compensator located on the first plane of the wavefront image, configured to partially or completely compensate for one or more components of the wavefront aberration, which allows more accurate measurement of the remaining (existing) component (s) wavefront aberrations. 14. The ophthalmic wavefront sensor according to claim 1, wherein the ophthalmic wavefront sensor is configured to be connected to an ophthalmic microscope. 15. The ophthalmic wavefront sensor according to claim 1, further comprising an eye image sensor configured to provide a live image of the front of the eye, and a second light guide element configured to provide an optical path for forming an image of the eye. 16. The ophthalmic wavefront sensor according to claim 15, further comprising a display configured to display a live image of the front of the eye with the imposition of a qualitative and / or quantitative wavefront measurement result. 17. The ophthalmic wavefront sensor according to claim 15, wherein the image sensor is further configured to provide information about the location of the eye pupil. 18. The ophthalmic wavefront sensor according to claim 1, further comprising a lens located between the matrix of partial wavefront selection elements and the matrix of two-dimensional position recording devices, configured to relay and optically increase the spacing between the image spots formed by the matrix of partial wavefront selection elements by the image spot plane, to the plane where the matrix of two-dimensional position recording devices is located. 19. The ophthalmic wavefront sensor according to claim 1, further comprising an electronic frequency-sensitive detection system coupled to receive a reference signal and a measurement signal, wherein the electronic frequency-sensitive detection system is configured to indicate only a magnitude of the frequency component of the measurement signal close to the reference frequency, which allows you to essentially suppress all noise signals, for example 1 / f noise, with f representing a constant signal and frequencies lower than the reference frequency. 20. An ophthalmic wavefront sensor, comprising: a first optical wavefront relay system configured to relay the wavefront reflected from the eye from the first object plane of the first optical wavefront relay system located on the front of the patient’s eye to the first wave image plane of the front of the first optical wavefront relay system along the first beam path, which can direct the incident wavefront relay beam to howl object plane to the first plane wavefront image;
a beam scanner / deflector located along the beam path, configured to completely intercept and scan the wavefront relay beam;
a matrix of two-dimensional position recording devices, wherein each two-dimensional position recording device is configured to detect a deviation of the centroid of the image spot from the reference position and output a measurement signal indicating the magnitude of the two-dimensional deviation; and
a matrix of partial wavefront selection elements located upstream of the matrix of two-dimensional position recording devices, each selection element in the matrix of partial wavefront selection elements is configured to select a partial wavefront of the relayed wavefront and focus the selected partial wavefront on the corresponding two-dimensional position recording device in the matrix two-dimensional position recording devices, the elements of the partial wavefront selection physically ki spaced from each other so that each selected partial wavefront of the wavefront reflected from the eye focuses only on the corresponding two-dimensional position registration device corresponding to selection of a partial element of the wavefront. 21. The ophthalmic wavefront sensor according to claim 20, further comprising:
a second wavefront optical relay system having a second object plane located essentially on the first wavefront image plane, configured to further relay the wavefront reflected from the eye from the second object plane to the second wavefront image plane along the second beam path which can direct the incident beam relay beam on the first object plane to the second image plane of the wave front;
moreover, the matrix of the elements of the selection of the partial wave front is located essentially on the second plane of the image of the wave front;
moreover, the scanner / beam deflector is located essentially in the second Fourier transform plane and is configured to completely intercept and scan the wavefront relay beam in two dimensions;
moreover, the matrix of elements of the selection of the partial wave front is located essentially in the second plane of the image of the wave front. 22. The ophthalmic wavefront sensor according to claim 20, wherein the first optical wavefront relay system includes a first and second lens, each lens having a diameter, a focal length and an optical axis, wherein the first optical wavefront relay system is capable of relaying the wavefront reflected from the eye from the first object plane located on the front of the patient’s eye to the first Fourier transform plane located between the first and second lenses and in a plane plane of the wavefront image along the first path of the beam, the focal lengths and diameters of the first and second lenses being selected to direct the beam of relaying the incident wavefront on the first object plane to the first plane of the wavefront image; and
in which the scanner / beam deflector is located essentially in the first Fourier transform plane located between the first and second lenses; and wherein the matrix of partial wavefront selection elements is located essentially in the first image plane of the wavefront. 23. The ophthalmic wavefront sensor according to claim 21, wherein the first optical wavefront relay system includes a first and second lens, each lens having a diameter, a focal length and an optical axis, the focal lengths and diameters of the first and second lenses being selected for the direction of the relay beam of the incident wave front on the first object plane to the first plane of the wavefront image; and
the second optical wavefront relay system includes a third and fourth lenses, each lens having a diameter, focal length and optical axis, focal lengths and diameters of the third and fourth lenses are selected for further direction of the incident wave relay relay beam on the first object plane to the second plane images of the wavefront. 24. Ophthalmic wavefront sensor according to any one of paragraphs. 20-23, further comprising:
a lens located between the matrix of partial wavefront selection elements and the matrix of two-dimensional position recording devices, configured to relay and optically increase the spacing between image spots formed by the matrix of partial wavefront selection elements on the image spot plane, to the plane where the matrix of two-dimensional registration devices is located provisions.

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