Apparatus for non-contact measurement of the group refractive index and geometric parameters of optical lenses and related measurement method

Abstract

This invention relates to an apparatus (1) for non-contact measurement of the group refractive index and / or geometric parameters and / or optical properties of an optical lens (3), referred to as a measuring apparatus, comprising: a support (2) intended to receive a sample (3, 7); and two optical heads (4, 5), each arranged at a known distance from the support on one side of the support such that the optical axis (41) of one optical head substantially coincides with the optical axis (51) of the other optical head. The two optical heads are capable of collecting at least one light beam (412, 512) reflected by one surface (31, 32) of the optical lens intended to rest on the support, and at least one light beam reflected by the other surface of the optical lens intended to rest on the support. The measuring apparatus includes an optical system (8) coupled to the optical heads and arranged to emit one or more light beams propagating to one or each of the optical heads, and to detect and analyze at least two light beams reflected by the optical lens and collected by one or more optical heads by interferometry. The measuring device includes a processing unit (6) which is arranged and / or programmed and / or configured to determine the optical group refractive index of the optical lens and / or the group refractive index gradient within the optical lens and / or at least one geometry-related parameter and / or at least one optical property-related parameter based on calibration data of the measuring device, based on one or more emitted beams and based on at least two beams reflected by the optical lens and collected by one or more optical heads.

Description

Technical Field

[0001] This invention relates to the field of optical lens characterization. Specifically, it relates to the characterization of polymer optical lenses, and more particularly to the characterization of polymer optical lenses obtained by molding.

[0002] This invention relates to the measurement and determination of the geometric parameters, group refractive index, and group refractive index gradient of optical lenses.

[0003] This invention is applied to the pilot production and manufacturing of optical lenses. It is also applied to the manufacturing and assembly of optical objectives. Background Technology

[0004] The actual geometry and optical properties of manufactured lenses, especially polymer lenses manufactured by molding, often do not perfectly match the expected or desired geometry and optical properties. This is because the molding process introduces or creates shape defects in the manufactured lens, which are obtained relative to the theoretical or expected shape.

[0005] Compared to the theoretically desirable lens, factors such as plastic shrinkage, mold machining precision, and functional clearances in mold component guidance can all contribute to defects in the geometry and optical properties of the manufactured lens. Similarly, the quality of the plastic used and its injection molding method (temperature, pressure, cooling cycle time) can also cause differences in refractive index between the design and production, or between different parts of the lens.

[0006] In addition, the anti-reflective coating is also a source of variation in the effective thickness of the lens obtained after treatment.

[0007] Optical lenses, such as those in camera modules, typically comprise assemblies of multiple lenses. These imperfections or defects mean that the optical components contain optical flaws compared to the shape anticipated during the design phase and the actual refractive index achieved. Defects contained within the manufactured lenses cause the objective lens's optical response to differ from expectations. In practice, defects present in manufactured lenses can lead to differences in point spread function (PSF), chromatic aberration, and geometric aberrations. Furthermore, because the pixel density of current camera module sensors is very close to the wavelength of light (which is itself less than one micrometer), manufacturing defects approaching or below one micrometer can have a significant impact at the sensor pixel level. However, maintaining such precision is difficult.

[0008] Devices and methods for characterizing optical lenses are known from the prior art. However, these measurements rely on measuring and / or acquiring a reference point on a reference plane, typically on a support on which the optical lens rests, while the optical lens is being measured.

[0009] One object of the present invention is to provide an apparatus and related method for non-contact measurement of the optical properties and / or refractive index and / or geometric parameters of an optical lens:

[0010] - Simplify measurement, and / or

[0011] - More versatile because they can measure the characteristics of multiple optical lenses in a production line manner, and / or

[0012] - Used to at least partially measure and characterize the geometry of the lens, i.e., the outer surface of the lens, and / or

[0013] - Used to measure and characterize the geometry of the lens at a set of characteristic locations on its outer surface, and / or

[0014] - At least one parameter used to measure and characterize the optical properties of a lens, or related to the optical properties of a lens, and / or

[0015] - Used to measure and characterize the group refractive index of a lens, and / or

[0016] - Used to perform at least partially the measurement and characterization without operating the lens during the measurement phase, and / or

[0017] - Regardless of the number of lenses to be characterized, no calibration step is required or a single calibration step is included.

[0018] Overview of the Invention

[0019] To this end, a device for non-contact measurement of the group refractive index and / or geometric parameters and / or optical properties of optical lenses is proposed, referred to as the measuring device. The measuring device includes:

[0020] - A support structure designed to receive a sample or to which a sample is intended to be mounted or placed.

[0021] - Two optical heads are arranged on both sides of the support at a known, preferably constant or unchanging distance from each other, such that the optical axis of one optical head is substantially coincident with the optical axis of the other optical head.

[0022] These two optical heads can be arranged to guide the incident beam, respectively.

[0023] Each of the optical heads is capable of or arranged to collect at least one light beam reflected from one of the surfaces of an optical lens intended to be placed on a support, and at least one light beam reflected from the other of the surfaces of an optical lens intended to be placed on a support.

[0024] The measuring device includes an optical system coupled to an optical head and arranged as follows:

[0025] - Firing one or more beams of light that propagate to one or each of the optical heads.

[0026] - Detect and analyze at least two light beams reflected by optical lenses and collected by one or more optical heads using interferometry.

[0027] The measuring device or optical system includes a processing unit arranged and / or programmed and / or configured to: determine the group refractive index (denoted as n) of the optical lens based on calibration data of the measuring device, based on one or more emitted light beams, and based on at least two light beams reflected by the optical lens and collected by one or more optical heads. lent ( ) and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

[0028] In this application, the group refractive index n lent It can be understood as: the group refractive index derived from the refractive index.

[0029] In this application, the group refractive index n lent Preferably, it refers to the group refractive index value derived from the refractive index. The group refractive index n of an optical lens... lent The group refractive index is determined based on the group velocity of the beam envelope, while the refractive index is determined based on the phase velocity of the beam. Group refractive index n lent It can be defined as an index that indicates the delay in the propagation of light energy.

[0030] Preferably, the method further determines the group refractive index based on the refractive index or its gradient. The value of the refractive index is very close to the value of the group refractive index.

[0031] The support may include means for fixing the optical lens.

[0032] The sample can be an optical lens or a standard part.

[0033] Preferably, the sample is not part of the measuring device.

[0034] Preferably, the distance between the optical heads is constant, or it can vary by a known value between two consecutive measurements or within the time interval between two consecutive measurements, preferably performed on two separate samples. Preferably, the distance between the optical heads is constant during the measurement.

[0035] Preferably, the incident beam from each optical head propagates along the optical axis of the optical head from which it originates.

[0036] The processing unit can be arranged and / or programmed and / or configured to control and / or command the optical system.

[0037] According to the present invention, the light beam reflected by the surface of the optical lens can be understood as the portion of the incident light beam reflected by the surface of the optical lens.

[0038] Preferably, at least two light beams reflected by the optical lens and collected by one or more optical heads are used (the processing unit is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens based on the at least two light beams reflected by the optical lens and collected by one or more optical heads). lent (and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens) includes at least one beam of light collected by one of the optical heads and reflected by a surface of the optical lens positioned facing another optical head.

[0039] Preferably, at least two light beams reflected by the optical lens and collected by one or more optical heads are used (the processing unit is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens based on the at least two light beams reflected by the optical lens and collected by one or more optical heads). lent (and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens) includes at least one light beam reflected by a given surface of the optical lens and collected by an optical head facing said given surface of the optical lens, and at least one light beam reflected by a surface of the optical lens opposite to the given surface and collected by an optical head facing said opposite surface of the optical lens.

[0040] Preferably, at least one parameter related to the geometry of the optical lens includes the thickness (d3) of the optical lens. lent ).

[0041] Preferably, at least one parameter related to the optical properties of the optical lens includes the optical path length (E) separating the two surfaces of the optical lens. lent ).

[0042] Preferably, optical path E lent Also known as optical distance E lent .

[0043] Preferably, according to an improvement of the device, one or each of the optical heads is also capable of or arranged to collect at least one light beam transmitted through an optical lens intended to be placed on a support.

[0044] Preferably, according to an improvement of the device, the optical system is arranged to also detect at least one beam of light that has passed through an optical lens and is collected by one of the optical heads.

[0045] Preferably, the processing unit is arranged and / or programmed and / or configured to also determine the group refractive index n of the optical lens based on at least one beam transmitted through the lens and collected by one of the optical heads. lent And / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

[0046] Preferably, the measuring device includes means for moving the support and the two optical heads relative to each other.

[0047] The device for relative motion can be arranged to move the support relative to the optical head, or conversely, to move the optical head relative to the support, or to move the support and the optical head relative to each other.

[0048] Preferably, the means for relative motion is arranged to generate relative motion between the optical head and the support relative to each other, at least in the plane in which the support extends or along the plane in which the support extends. Preferably, each optical head and / or support is arranged to be tilted and / or oriented and / or deflected. Preferably, each optical head is arranged to be tilted and / or oriented and / or deflected such that the optical axis of one optical head substantially coincides with the optical axis of the other optical head, preferably always.

[0049] Preferably, the support is a device for relative motion, which is arranged to control and / or adjust and / or modulate the relative position of the support with respect to the optical head, and conversely, modulate the relative position of the optical head with respect to the support such that the distance between the optical heads is constant.

[0050] Preferably, the means for relative motion is arranged to generate relative translational and / or rotational motion between the support and the optical heads. Preferably, the measuring device is arranged to perform the following steps: collecting at least two reflected beams and / or at least one transmitted beam for multiple relative positions of the support relative to the two optical heads.

[0051] Preferably, the means for relative motion is arranged to translate and / or rotate the support and the optical head relative to each other between two consecutive measurements.

[0052] According to another aspect of the invention, a group refractive index n for non-contact measurement optical lenses is also proposed. lentMethods involving and / or geometric parameters and / or optical properties are called measurement methods. A measurement method includes the following steps: emitting one or more light beams through the optical system of the measuring device; the emitted light beams, or each emitted light beam, propagating to discrete optical heads, each of which is arranged to guide the incident light beams; two optical heads are arranged on opposite sides of a support at a known, constant, or invariant distance from each other, such that the optical axis of one optical head substantially coincides with the optical axis of the other optical head; and a sample is placed on the support.

[0053] The measurement method also includes the step of detecting at least two light beams reflected by optical lenses and collected by one or more optical heads via an optical system.

[0054] The measurement method also includes determining the group refractive index n of the optical lens by a processing unit based on one or more emitted light beams and at least two light beams reflected by the optical lens and collected by one or more optical heads. lent The steps of and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

[0055] Preferably, the group refractive index n of the optical lens is determined. lent and / or the group refractive index gradient within the optical lens and / or parameters related to at least one optical lens geometry (e.g., the thickness of the optical lens (d3)). lent ()) and / or at least one parameter related to the optical properties of the optical lens (e.g., the optical path length separating the two surfaces of the optical lens (E) lent The steps are implemented based on at least two optical distances, which are derived from:

[0056] - Optical distance Z4 lent31 And optical distance Z5 lent32 For each corresponding optical head, the optical distance Z4 lent31 And optical distance Z5 lent32 The sum of the optical distance traveled by the incident beam from the given optical head to the surface of the optical lens facing the given optical head, and the optical distance traveled by the reflected beam from the surface of the optical lens facing the given optical head to the given optical head, and

[0057] - Optical distance Z4 lent32 And optical distance Z5 lent31 For each corresponding optical head, the optical distance Z4 lent32 And optical distance Z5 lent31This corresponds to the sum of the optical distance traveled by the incident beam from a given optical head to the surface of the optical lens opposite to the given optical head, and the optical distance traveled by the reflected beam from the surface of the optical lens opposite to the given optical head to the given optical head.

[0058] Measuring equipment and / or optical systems may be arranged, and / or processing units may be arranged and / or programmed and / or configured to analyze and / or process and / or determine and / or measure and / or calculate optical distance Z4 based on one or more emitted light beams and / or at least two light beams reflected by optical lenses and collected by one or more optical heads. lent31 Z4 lent32 Z5 lent32 and Z5 lent31 .

[0059] Preferably, the determining step includes one or more linear combinations of at least two reflected beams. Preferably, the determining step includes one or more linear combinations of at least two optical distances traveled by at least two reflected beams.

[0060] The determination step may include one or more linear combinations of the two reflected beams. Preferably, the determination step may include one or more linear combinations of the two optical distances traveled by the two reflected beams.

[0061] The determination step may include one or more linear combinations of the four reflected beams. Preferably, the determination step may include one or more linear combinations of the four optical distances traveled by the four reflected beams.

[0062] Preferably, the optical path E of the two surfaces of the separating optical lens lent It can be defined as the refractive index of an optical lens (denoted as n). lent The physical distance (denoted as d3) traveled within the optical lens between the incident beam and / or the reflected portion of the incident beam. lent The product of ).

[0063] The optical path E of the two surfaces of the separating optical lens lent It can be determined based on at least two reflected beams, preferably only and / or directly based on at least two reflected beams, and denoted as E. lent(re) .

[0064] Preferably, the determining step includes calculating the optical path length of the two surfaces separating the Ellent optical lens according to Equation 1.

[0065] Equation 1

[0066] Where ΔZ1 equals Z4 lent32 -Z4 lent31 ΔZ2 equals Z5 lent31-Z5 lent32 ,

[0067] a and b are real numbers, and

[0068] E lent(re) The optical path E is the distance between the two surfaces of the optical lens. lent E lent(re) Determined based on at least two reflected beams.

[0069] Preferably, ΔZ1 and ΔZ2 are the difference of the following:

[0070] - The incident beam from the given optical head to the relative optical lens surface of the given optical head, and the optical distance traveled by the reflected beam from the relative lens surface of the given optical head to the given optical head, and...

[0071] - The optical distance traveled by the incident beam from a given optical head to an optical lens surface facing the optical head, and by the reflected beam from the optical lens surface facing the given optical head to the given optical head.

[0072] Preferably, the determining step includes calculating the optical path E of the two surfaces of the separating optical lens according to Equation 2. lent ,

[0073] Equation 2

[0074] Where ∑ZX is different from ∑ZY, and ∑ZX and ∑ZY are equal to ∑Z1, ∑Z2, ∑Z2' or ∑Z3.

[0075] ∑Z1 equals Z5 lent32 +Z4 lent31 ,

[0076] ∑Z2 equals Z4 lent31 +Z5 lent31 ∑Z2' equals Z4 lent32 +Z5 lent32 ,

[0077] ∑Z3 equals Z5 lent31 +Z4 lent32 ,and

[0078] e and f are real numbers.

[0079] Preferably, ∑Z1 is the sum of the following terms:

[0080] - The incident light beam travels from the given optical head to the surface of the optical lens facing the given optical head, and the reflected light beam travels the optical distance from the surface facing the given optical head to the given optical head.

[0081] - The optical distance traveled by the incident beam from one optical head to the surface of the optical lens facing the other optical head, and by the reflected beam from the surface of the optical lens facing the other optical head to the other optical head.

[0082] Preferably, ∑Z2 or ∑Z2' is the sum of the following terms:

[0083] - The incident light beam travels from the given optical head to the surface of the optical lens facing the given optical head, and the reflected light beam travels from the surface of the lens facing the given optical head to the given optical head, and

[0084] - The optical distance traveled by the incident beam from one optical head to the surface of the optical lens opposite to the other optical head, and by the reflected beam from the surface of the optical lens opposite to the other optical head to the other optical head.

[0085] Preferably, ∑Z3 is the sum of the following terms:

[0086] - The incident light beam travels from the given optical head to the surface of the optical lens opposite the given optical head, and the reflected light beam travels from the surface of the optical lens opposite the given optical head to the given optical head, and

[0087] - The optical distance traveled by the incident beam from one optical head to the surface of the optical lens opposite to the other optical head, and by the reflected beam from the surface of the optical lens opposite to the other optical head to the other optical head.

[0088] The advantage of the above optical path calculation is that it completely eliminates the need for calibration data. This is achieved by calculating the optical path E on both sides of the separating optical lens. lent This allows for the estimation and / or determination of the optical response and / or the quality of the optical response of an optical lens.

[0089] Preferably, the determining step includes calculating the thickness of the optical lens (denoted as d3) according to Equation 3. lent ):

[0090] Equation 3

[0091] Where u, v, w, x, and y are integers, rational numbers, or real numbers, and u + v + w + x = 1, and I is known data or data obtained through calibration.

[0092] C is the calibration data, and

[0093] d3 lent(re) The thickness of an optical lens is determined based on at least two reflected beams.

[0094] Preferably, .

[0095] Preferably, I is the group refractive index (denoted as na), which is derived from the refractive index in air or in the medium between the optical head and the corresponding surface of the optical lens at or near the measurement wavelength.

[0096] Preferably:

[0097] - The detection step also includes detecting at least one beam of light transmitted through an optical lens resting on the support and collected by one of the optical heads.

[0098] - The determination step is also based on at least one beam of light that has passed through an optical lens and is collected by one of the optical heads.

[0099] Preferably, the group refractive index n of the optical lens is determined. lent and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the optical lens geometry (e.g., the thickness d3 of the optical lens). lent And / or at least one parameter related to the optical properties of the optical lens (e.g., the optical path E separating the two surfaces of the optical lens). lent The steps are also implemented based on the optical distance traveled by the incident beam from the optical head, through the sample, to reach another optical head.

[0100] Preferably, the determining step includes one or more linear combinations of at least two reflected beams and at least one transmitted beam. Preferably, the determining step includes one or more linear combinations of at least two optical distances traveled by at least two reflected beams and at least one optical distance traveled by at least one transmitted beam.

[0101] The determination step may include one or more linear combinations of the following:

[0102] - Two reflected beams and one transmitted beam, or

[0103] - Two reflected beams and two transmitted beams.

[0104] Preferably, the determining step includes one or more linear combinations of the following:

[0105] - The two optical distances traveled by the two reflected beams and the one optical distance traveled by the transmitted beam, or

[0106] - The two optical distances traveled by the two reflected beams and the two distances traveled by the two transmitted beams.

[0107] Preferably, the determining step includes one or more linear combinations of the following:

[0108] - The three optical distances traveled by the two reflected beams and the one optical distance traveled by the transmitted beam, or

[0109] - The three optical distances traveled by the two reflected beams and the two optical distances traveled by the two transmitted beams.

[0110] The determination step may include one or more linear combinations of the following:

[0111] - Four reflected beams and one transmitted beam, or

[0112] - Four reflected beams and two transmitted beams.

[0113] Preferably, the determining step includes one or more linear combinations of the following:

[0114] - The four optical distances traveled by the four reflected beams and the one optical distance traveled by the transmitted beam, or

[0115] - The four optical distances traveled by the four reflected beams and the two optical distances traveled by the two transmitted beams.

[0116] Preferably, the determining step includes calculating the optical path length Elent of the two surfaces of the separating optical lens and / or the thickness d3 of the optical lens (3) according to Equation 4. lent :

[0117] Equation 4

[0118] ZT4 and ZT5 represent the optical distances traveled by the incident beam as it originates from one optical head, passes through the sample, and reaches the other optical head.

[0119] σ, p, q, r, and s are real numbers.

[0120] D and D' are calibration data.

[0121] d3 lent(tr) The thickness d3 of the optical lens is determined, in particular, based on at least one transmitted beam. lent And E lent(tr) It is specifically the optical path E of the two surfaces of the separating optical lens, determined according to at least one transmitted beam. lent .

[0122] Preferably, note that for σ = s, And for σ = -r, .

[0123] Preferably, when r or s is chosen to be zero, performing the determination step only requires d3. lent(re) or E lent(re) .

[0124] Preferably, I, C, D, and / or D' are data specific to, relating to, or dependent on the measuring device. Preferably, the group refractive index na is a constant and / or included in a table or database. I and na may be calibration data.

[0125] Preferably, the determining step includes calculating the group refractive index n of the optical lens according to Equation 5. lent ,

[0126] Equation 5.

[0127] Item E lent It can be any term E determined by combining the reflection measurement results according to Equation 1 or Equation 2. lent(re) Or, the term E derived from Formula 4. lent(tr) Item d3 lent It can be any term d3 obtained by combining one of the calculations based on the reflection measurement results according to Formula 3. lent(re) Or, the term d3 obtained from Formula 4. lent(tr) .

[0128] Of course, those skilled in the art will understand that the equations proposed for determining the group refractive index and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens are merely examples or specific embodiments. Those skilled in the art will know how to implement the determining steps through specific embodiments other than those shown in Equations 1 to 5.

[0129] Preferably, the optical distance is determined by optical coherence tomography (OCT).

[0130] Preferably, the method includes the step of generating relative translational and / or rotational motions of the support and the optical head relative to each other using means for relative motion.

[0131] Preferably, the method includes collecting at least two reflected beams and / or at least one transmitted beam at the following locations:

[0132] - The relative position of the support and the optical head that causes the optical axis of the optical head to coincide with the optical axis of the optical lens is called the center position, and

[0133] - At least one of the support and the optical head is positioned such that the intersection of the optical axis of the optical head and the lens is located in a relative position within the annular peripheral region of the lens, referred to as the assembly region, and / or

[0134] - At least one of the support and the optical head is positioned such that the intersection of the optical axis of the optical head and the lens is located between the assembly area and the center position.

[0135] Preferably, the method includes at least two thickness values ​​d3 of the optical lens calculated at at least two relative positions. lent and / or at least two optical paths E lent To determine the geometry of the optical lens.

[0136] The geometry of the lens can be determined based on the thickness d3 of the optical lens according to any embodiment described in this application. lent To determine.

[0137] Preferably, the method includes determining the group refractive index n of the optical lens based on at least two group refractive index values ​​calculated at at least two relative positions. lent The gradient.

[0138] The distance between two relative positions can be used to divide by the determined group refractive index n. lent The difference in values. The group refractive index gradient can be represented as a vector with two coordinates representing the two displacement directions. For each displacement, the group refractive index n of the optical lens... lent The difference can be divided by the length of the displacement to provide each of the two coordinates.

[0139] According to the invention, the measuring device according to the invention is suitable, more preferably particularly suitable, and more preferably designed and particularly advantageously designed specifically for implementing the measuring method according to the invention. Therefore, any feature of the measuring device according to the invention can be directly converted and integrated into the measuring method according to the invention, and conversely, any feature of the measuring method according to the invention can be directly converted and integrated into the measuring device according to the invention.

[0140] According to the present invention, a data processing apparatus is also proposed, comprising means arranged and / or programmed and / or configured to implement the method according to the present invention.

[0141] According to the present invention, a computer program is also provided, comprising instructions that, when executed by a computer, cause the computer to perform the method according to the present invention.

[0142] According to the present invention, a computer-readable medium (e.g., a recording medium) is also provided, which includes instructions that, when executed by a computer, cause the computer to perform the method according to the present invention.

[0143] According to the present invention, a computer-readable data medium having a computer program according to the present invention recorded thereon is also proposed.

[0144] The device according to the invention can be any type of device or integrated into any type of device, such as a smartphone, tablet computer, computer, calculator, processor, or computer chip, and said any type of device is programmed to implement the method according to the invention, for example by running a computer program according to the invention. Attached Figure Description

[0145] Other advantages and features of the invention will become apparent from a review of the detailed description of the fully non-limiting embodiments and examples, as well as the following drawings:

[0146] Figure 1 This is a schematic side view of an embodiment of the measuring device according to the present invention.

[0147] Figure 2 This is a schematic side view of an optical lens.

[0148] Figure 3 This is a schematic top view of an optical lens.

[0149] Figure 4 yes Figure 1 The schematic side view of the example measuring device illustrates different optical distances traveled by the reflected beam between the optical lens and the optical head.

[0150] Figure 5 yes Figure 1 The schematic side view of the measuring device in the example illustrates the different optical distances the reflected beam travels between the standard and the optical head. Detailed Implementation

[0151] The embodiments described below are by no means limiting, and variations of the invention may be contemplated in particular, including only feature selections separate from the other disclosed features (even if such selection is separated within a phrase containing other features), provided that such feature selection is sufficient to provide a technical advantage or to distinguish the invention from the prior art. Such selection may include at least one preferred functional feature (lacking structural details), or only a portion of structural details, provided that portion is sufficient to provide a technical advantage or to distinguish the invention from the prior art.

[0152] refer to Figure 1 This presents the method according to the invention for measuring the group refractive index n of an optical lens. lent An embodiment of a non-contact measuring device 1 for and / or geometric parameters and / or optical properties.

[0153] The measuring device 1 includes a support 2 designed to receive samples 3, 7. The support 2 can be arranged to receive multiple samples 3, 7 simultaneously. The support 2 may include at least one transparent opening 21 and / or window (21), and the samples 3, 7 are intended to be arranged within or facing the transparent opening 21 and / or window.

[0154] The measuring device 1 includes two optical heads 4 and 5, each arranged at a constant distance from the other. During measurement, the distance between the optical heads 4 and 5 and the support member 2 should remain constant. The optical heads 4 and 5 are arranged on opposite sides of the support member 2 such that the optical axis 41 of one optical head 4 and 5 substantially coincides with the optical axis 51 of the other optical head 4 and 5. During measurement, the optical axes 41 and 51 of the optical heads 4 and 5 must remain substantially identical. The two optical heads 4 and 5 are arranged to guide incident light beams 411 and 511, respectively.

[0155] Each optical head 4, 5 is capable of collecting at least one light beam 412, 512 reflected by one surface 31, 32 of the optical lens 3 intended to be placed on the support 2, and at least one light beam 412, 512 reflected by the other surface 31, 32 of the optical lens 3 intended to be placed on the support 2.

[0156] The measuring device 1 includes an optical system 8 coupled to each optical head 4, 5. The optical system 8 is arranged to emit one or more light beams propagating to the optical heads 4, 5. The optical system 8 is also arranged to detect and analyze the light beams from the optical heads 4, 5 by interferometry, particularly at least two light beams 412, 512 reflected by the optical lens 3 and collected by one or more optical heads 4, 5.

[0157] The measuring device includes a processing unit 6, which is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens 3 based on calibration data from the measuring device 1, one or more emitted light beams, and at least two light beams 412, 512 reflected by the optical lens 3 and collected by one or more optical heads 4, 5. lent The group refractive index gradient within the optical lens 3 and / or at least one parameter related to the geometry and / or optical properties of the optical lens 3. The group refractive index of the optical lens 3, the group refractive index gradient within the optical lens 3, and at least one parameter related to the geometry and / or optical properties of the optical lens 3 will be referred to as the “characteristics” of the optical lens 3.

[0158] A feature of interest related to the geometry of optical lens 3 is the optical path E separating the two surfaces 31 and 32 of optical lens 3. lent .

[0159] Another feature of interest related to the geometry of optical lens 3 is its thickness d3. lent .

[0160] According to a non-limiting embodiment, the characteristics of the optical lens 3 are determined by comparing or analyzing the optical distances traveled by at least two light beams 412, 512 reflected by the optical lens 3.

[0161] Optical distance (denoted as n*d) can be expressed as the product of the refractive index (n) of the medium (in which the light beam propagates) and the physical distance (d) that the light beam travels in the medium.

[0162] According to a non-limiting embodiment, the optical distance is determined by optical coherence tomography (OCT).

[0163] In this configuration, each beam 412, 512 reflected by the optical lens 3 will be detected by the optical system 8 as a peak corresponding to the optical distance traveled by the beam from its emission point to its reception by the optical system 8. Therefore, two discrete reflected beams 412, 512 will be detected as two discrete peaks. The gap between the positions of these two peaks will allow the optical distance between the peaks to be obtained, corresponding to the difference in the optical distances traveled by the two discrete reflected beams 412, 512.

[0164] Since the distance between optical heads 4 and 5 is known and fixed during measurement, the optical distance the beam travels between the optical system 8 and each optical head 4 and 5 is the same during measurement. Therefore, the difference between the optical distances traveled by the beams emitted and detected by the optical system 8 stems only from the difference in the optical distances traveled by the incident beams 411 and 511 and the reflected beams 412 and 512.

[0165] However, the distance between the optical heads 4 and 5 and the support 2 between the two measurements can vary with a known value.

[0166] The reflected beams 412 and 512 that can be detected by optical system 8 are:

[0167] - The light beam 412 reflected by the surface 31 of lens 3 and collected by optical head 4,

[0168] - The light beam 412 is reflected by the surface 32 of the lens 3 and collected by the optical head 4.

[0169] - The light beam 512 reflected by the surface 32 of the lens 3 and collected by the optical head 5.

[0170] - The light beam 512 is reflected by the surface 31 of the lens 3 and collected by the optical head 5.

[0171] Therefore, the beneficial optical distance that can be determined is:

[0172] - Optical distance Z4 lent31 And optical distance Z4 lent32 These correspond to the sum of the optical distances traveled by the incident beam 411 emitted by the optical system 8 from the given optical head 4 to the surface 31 or 32 of the optical lens 3, and the optical distances traveled by the incident beam 411 from the surface 31 or 32 of the optical lens 3 to the reflecting portion 412 of the given optical head 4, respectively.

[0173] - Optical distance Z5 lent32 And optical distance Z5 lent31 These correspond to the sum of the optical distances traveled by the incident beam 511 emitted by the optical system 8 from the optical head 5 to the surface 32 or 31 of the optical lens 3, and the optical distances traveled by the incident beam 511 from the surface 32 or 31 of the optical lens 3 to the reflecting portion 512 of the optical head 5.

[0174] In practice, the “total” optical distance actually measured by optical system 8 and / or measuring device 1 also includes a given round-trip optical distance between optical heads 4 and 5 and a reference of optical system 8 and / or measuring device 1, denoted as OffsR4 (from optical head 4 to optical head 5) and OffsR5 (from optical head 5 to optical head 4). This given optical distance corresponds to the path of the emitted and reflected beams in measuring device 1 and / or the emitted and reflected beams by optical system 8 from it to the internal reference.

[0175] It can also be noted that na is the group refractive index obtained from the group refractive index of air at the wavelength of the incident beam.

[0176] Special Reference Figure 4 and Figure 5 The incident beam 411 and the beam 412 reflected by the surface 31 of the lens 3 and collected by the optical head 4 travel an optical distance Z4. lent31 The incident beam 411 and the beam 412 reflected by the surface 31 of the lens 3 and collected by the optical head 4 travel a corresponding physical distance—the physical distance d1 between the optical head 4 and the surface 31 of the optical lens 3. lent Or the physical distance d1 between the optical head 4 and the surface 71 of the standard part 7. étal Unless otherwise specified, the distance denoted as d1 corresponds to the physical distance d1. lent and / or physical distance d1 étal Optical distance Z4 lent31 The relationship between the distance d1 and the distance d1 can be expressed as: , where na is the group refractive index of air at the wavelengths of the one or more incident beams 412, 512.

[0177] The incident beam 411 and the beam 412 reflected by the surface 32 of the lens 3 and collected by the optical head 4 travel an optical distance Z4. lent32 The incident beam 411 travels a physical distance d1, and the beam 412, reflected by the surface 32 of the lens 3 and collected by the optical head 4, travels a corresponding physical distance d1 and twice that physical distance d3. lent and / or twice the physical distance d3 etal Unless otherwise specified or stated, the distance denoted as d3 corresponds to the physical distance d3. lent and / or physical distance d3 étal Optical distance Z4 lent32 The relationship between distance d3 and sample 3 and sample 7 can be expressed as follows: ,or .

[0178] The same form is used for the incident beam 511 and the beam 512 reflected by the surface 32 of the lens 3 and collected by the optical head 5, wherein the optical distance Z5 lent32 and physical distance d2 (d2 can refer to d2) lent and / or d2 étal The same form is also used for the incident beam 511 and the beam 512 reflected by the surface 31 of the lens 3 and collected by the optical head 5, with an optical distance Z5. lent31 Physical distance d2 and physical distance d3.

[0179] The characteristics of the optical lens 3 are determined by the processing unit 6 based on the following beams (or in other words, at least two beams 412, 512 that determine the characteristics of the optical lens 3 include):

[0180] - At least one light beam 412 or 512 reflected by a given surface 31 or 32 of the optical lens 3 and collected by an optical head 4 or 5 facing the given surface 31 or 32 of the optical lens 3, respectively, and

[0181] - At least one light beam 512 or 412 reflected by a surface 32 or 31 opposite to a given surface of the optical lens 3 and collected by an optical head 5 or 4 facing the opposite surface 32 or 31 of the optical lens 3, and / or

[0182] - At least two reflected light beams 412, 512, at least one of which has been reflected by the surfaces 31, 32 of the optical lens 3 opposite to the optical heads 4, 5, and the at least one reflected light beam 412, 512 is collected by the optical heads 4, 5.

[0183] According to an advantageous embodiment, the processing unit 6 determines one or more characteristics of the optical lens 3, including one or more linear combinations of at least two optical distances.

[0184] The processing unit 6 determines one or more characteristics of the optical lens 3, including calculating the optical path length E. lent As a non-limiting example, the optical path E lent Calculation can be performed according to Equation 1:

[0185] Equation 1

[0186] Where ΔZ1 equals Z4 lent32 - Z4 lent31 ΔZ2 equals Z5 lent31 - Z5 lent32 ,and

[0187] a and b are real numbers such that a + b = 0.5.

[0188] How to use E1 to directly calculate E based on the two reflected beams 412 and 512 lent Two simple, non-limiting specific examples of data that do not require calibration are: E lent = 0.5 * ΔZ1 (a = 0.5 and b = 0) and E lent = 0.5 * ΔZ2 (a =0 and b = 0.5).

[0189] Optical path E lent It can also be calculated according to Equation 2:

[0190] Equation 2

[0191] Where ∑ZX ≠ ∑ZY, and ∑ZX and ∑ZY are equal to ∑Z1, ∑Z2, ∑Z2' or ∑Z3.

[0192] ∑Z1 equals Z5 lent32 + Z4 lent31 ,

[0193] ∑Z2 equals Z4 lent31 + Z5 lent31 ∑Z2' equals Z4 lent32 + Z5 lent32 ,

[0194] ∑Z3 equals Z5 lent31 + Z4 lent32 ,and

[0195] e and f are real numbers such that e = f.

[0196] Optical path E lent The calibration-free data is also calculated according to Formula 2. Depending on the specific situation, two or four reflected beams 412 and 512 can be used to calculate the optical path E according to Formula 2.lent .

[0197] A simple, non-restrictive example of directly calculating Elent according to Equation 2 is given:

[0198] ∑Z3 - ∑Z1 = 2*(ΔZ1 + ΔZ2) = 2*(2*E lent ), where e = 0.25 and E lent = e*(∑Z3- ∑Z1),

[0199] ∑Z3 - ∑Z2 = ΔZ1 = 1*(2*E lent ), where e = 0.5 and E lent = e*(∑Z3 - ∑Z2),

[0200] ∑Z3 - ∑Z2' = ΔZ2 = 1*(2*E lent ), where e = 0.5 and E lent = e*(∑Z3 - ∑Z2'),

[0201] ∑Z2 - ∑Z1 = ΔZ2 = 1*(2*E lent ), where e = 0.5 and E lent = e*(∑Z2 - ∑Z1),

[0202] ∑Z2' - ∑Z1 = ΔZ1 = 1*(2*E lent ), where e = 0.5 and E lent = e*(∑Z2' - ∑Z1).

[0203] Those skilled in the art will readily recognize that certain combinations cannot be used to determine the steps, for example:

[0204] ∑Z2' - ∑Z2 = 0*(2*E lent ).

[0205] Each optical distance Z4 lent31 Z4 lent32 Z5 lent31 and Z5 lent32 It can be rewritten as:

[0206] ,

[0207] ,

[0208] ,

[0209] .

[0210] Those skilled in the art will be able to rewrite Equations 1 and 2, and any expressions derived therefrom, using this notation, and will in particular note that terms with OffsR4, OffsR5, 2*(na*d1), and 2*(na*d2) cancel each other out in the aforementioned combinations, thus yielding expression E. lent .

[0211] Determine the optical path length E lent The advantage is that, according to the present invention, it is directly deterministic, requires only two measurements (at least), and does not require calibration or calibration data.

[0212] Optical path E lent It is also useful in optical lens production lines. Optical path E lent This allows direct control over the integral of the product of the local lens thickness and the local optical refractive index encountered at the optical lens thickness. This directly relates to the curvature effect of the optical wavefront transmitted through the lens. Therefore, the optical path E is determined. lent It is very useful for characterizing the deviation between lens manufacturing and design.

[0213] The processing unit 6 determines one or more characteristics of the optical lens 3, including calculating the thickness d3 of the optical lens 3 according to Equation 3. lent :

[0214] Equation 3

[0215] Where u, v, w, x, y, and I are integers, rational numbers, or real numbers, and u + v + w + x = 1, and

[0216] C is the calibration data, and I = na.

[0217] According to this embodiment, However, choosing other references, other conventions, or other optical distances will result in weighting.

[0218] This shows how to directly calculate d3 according to Equation 3. lent Simple, non-restrictive specific examples: (where u = 1, and v = w = x = 0). (where v = 1, and u = w = x = 0). (where w = 1, and u = v = x = 0), or even Where x = 1, and u = v = w = 0).

[0219] I is correlated and depends on the measuring device used. According to this embodiment, I equals na.

[0220] The calibration data C can be measured on standard part 7 by interferometry, or it can be determined by simulation model.

[0221] As a non-limiting example, calibration data includes data using one or more known optical refractive indices and thicknesses d3. etal The data is obtained by calibrating standard component 7. This data may be stored calibration data. In this case, no additional calibration is required during the implementation of the method. Those skilled in the art will understand that this calibration data can be obtained during the implementation of the method if there is a specific need.

[0222] The calibration data C can be equal to: .

[0223] It is equal to twice the known optical path length of the two surfaces of the standard component 7.

[0224] Z4 étal31 The measured optical distance traveled by the incident beam 411 emitted by the optical system 8 from the given optical head 4 to the surface 71 of the standard 7 is the sum of the measured optical distance traveled by the reflected portion 412 of the incident beam 411 from the surface 71 of the standard 7 to the given optical head, and Z5 étal32 The measured optical distance traveled by the incident beam 511 emitted by the optical system 8 from the given optical head 5 to the surface 72 of the standard 7 is the sum of the measured optical distance traveled by the reflected portion 512 of the incident beam 511 from the surface 72 of the standard 7 to the given optical head.

[0225] refer to Figure 3 and Figure 4 The physical distance between the surface 31 of the separating optical head 4 and the optical lens 3 is denoted as d1. lent The physical distance between the optical head 4 and the surface 71 of the standard part 7 is denoted as d1. étal The physical distance between the separating optical head 5 and the surface 32 of the optical lens 3 is denoted as d2. lent The physical distance between the optical head 4 and the surface 72 of the standard part 7 is denoted as d2. étal The physical distance between surfaces 31 and 32 of the separating optical lens 3 is denoted as d3. lent The physical distance between face 72 and face 72 of the separating standard part 7 is denoted as d3. étal n a n lent and n étal The group refractive indices correspond to those of air, optical lens 3, and standard component 7, respectively.

[0226] Therefore, the following equation can be written:

[0227] ,

[0228] ,

[0229] ,

[0230] .

[0231] When the distance between the optical heads is constant or unchanging, we have Because of the distance and (d1) étal + d2 étal + d3 étal ) and (d1 lent + d2 lent + d3 lent The distance between the two optical heads 4 and 5 is equal to the distance between them.

[0232] If the distance between optical heads 4 and 5 changes, for example, between calibration and measurement of samples 3 and 7, and the change is Δz (Δz is considered positive if the distance increases during calibration), then it should be included in the calculation of C, according to... To remove the change Δz. Then we have .

[0233] According to a non-limiting embodiment, Z4 étal31 and Z5 étal32 The calibration measurement set is obtained at a single location or optionally at multiple locations prior to measuring the optical lens 3. The calibration measurement set is independent of sample 3. This method eliminates the need for further calibration when measuring calibration data. It also eliminates the need for a reference in the measuring apparatus for each measurement of the optical lens 3.

[0234] According to an improvement of the device, the optical heads 4 and 5 are also capable of collecting at least one light beam 413 or 513 that has passed through the optical lens 3 intended to be placed on the support 2. The optical system 8 is also arranged to detect at least one light beam 413 or 513 that has passed through the optical lens 3 and has been collected by one of the optical heads 4 and 5.

[0235] Therefore, the characteristics of the optical lens 3 can be determined by the processing unit 6 based on at least one transmitted beam 413, 513 and at least two reflected beams 412, 512.

[0236] According to this embodiment, determining one or more characteristics of the optical lens 3 includes one or more linear combinations of at least two optical distances traveled by at least two reflected beams 412, 512 and at least one optical distance traveled by at least one transmitted beam 413, 513.

[0237] The processing unit 6 determines one or more characteristics of the optical lens 3, including calculating the optical path E separating the two surfaces of the optical lens according to Equation 4. lent and / or the thickness d3 of optical lens 3 lent :

[0238] Equation 4

[0239] ZT4 and ZT5 represent the optical distances traveled by incident beams 411 and 511 from optical head 4 through sample 3 to another optical head 5, respectively.

[0240] σ, p, q, r, and s are real numbers.

[0241] D and D' are calibration data.

[0242] d3 lent(tr) Specifically, the thickness d3lent of the optical lens 3 is determined according to at least one transmitted light beam 413, 513, and

[0243] E lent(tr) Specifically, the optical path E of the two surfaces 31 and 32 of the separating optical lens 3 is determined according to at least one transmitted beam 413, 513. lent .

[0244] According to Equation 4, for σ = s, And for σ = -r, .

[0245] Similar to OffsR4 and OffsR5, the “total” optical distance actually measured by the optical system 8 and / or measuring device 1 also includes a given optical distance between optical heads 4 and 5 and a reference of the optical system 8 and / or measuring device 1, denoted as OffsT4 (from optical head 4 towards optical head 5) and OffsT5 (from optical head 5 towards optical head 4). This given optical distance corresponds to the path of the light beam emitted and transmitted by the optical system 8 within the measuring device 1 to the detector or internal reference point.

[0246] Therefore, the following equation can be written:

[0247] ,

[0248]

[0249] ,and

[0250] ,

[0251] ,and

[0252] .

[0253] The calibration data D (and / or D') can be measured by interferometry on standard 7 or in the absence of samples 3 and 7, or determined by simulation model.

[0254] According to the second alternative, the calibration data D (and / or D') is obtained by a single measurement performed by the measuring device 1 before measuring the optical lens 3.

[0255] The processing unit 6 determines one or more characteristics of the optical lens 3, including calculating the group refractive index n of the optical lens 3. lent As a non-limiting example, the group refractive index n of optical lens 3 lent Calculate according to Equation 5:

[0256] Equation 5.

[0257] The advantage of this invention is that the characteristics of the optical lens 3 can be directly obtained by measuring the optical distance.

[0258] Regarding the determination of the group refractive index n of an optical lens lent and / or the gradient of the group refractive index within the optical lens and / or at least one parameter related to the geometry of the optical lens (e.g., the thickness d3 of the optical lens). lent And / or at least one parameter related to the optical properties of the optical lens (e.g., the optical path E separating the two surfaces of the optical lens). lent All embodiments (and formulas) described herein are non-limiting but constitute only advantageous embodiments. Those skilled in the art will be able to determine other determining embodiments based on the teachings given in this specification. In particular, understanding and / or measuring distances d1 and d2 opens up many other ways to implement the determining steps.

[0259] In cases where D and D' are obtained by measurement on standard 7 or in the absence of samples 3 and 7, they are obtained by a single measurement performed by measuring device 1 before measuring optical lens 3. This method thus eliminates the need for calibration when measuring calibration data. It also eliminates the need for a reference in the measuring device that must be used for each measurement of optical lens 3 whose characteristics are to be determined.

[0260] Another advantage of the second variant is that the intensity of at least one beam collected by transmission is very high, especially compared to the intensity of a beam collected by reflection.

[0261] Optical path E of optical lens 3 lentOr thickness d3 lent It can be calculated as multiple optical path lengths E obtained through different calculations or determinations. lent Or thickness d3 lent The average value of .

[0262] Optical path E of optical lens 3 lent Or thickness d3 lent The calculation can be performed by weighting the contributions of the following items, based on one of the non-limiting formulas or one of the calculated or determined non-limiting embodiments:

[0263] - Two reflected beams 412, 512, and / or

[0264] - Three reflected beams 412, 512, and / or

[0265] - Four reflected beams 412, 512, and / or

[0266] - One or more transmitted beams 413, 513.

[0267] The advantage of the measuring device 1 and method according to the present invention compared with the prior art measuring devices is that it does not require performing a reference measurement while measuring the optical lens whose characteristics are to be determined.

[0268] According to an improvement of the present invention, the measuring device 1 includes means for moving the support 2 and the two optical heads 4, 5 relative to each other.

[0269] The device for relative motion can be arranged to change the distance between the optical heads 4 and 5 and the support 2. It is preferred that the support and the optical heads 4 and 5 be equidistant.

[0270] The means for relative motion is also arranged to translate and / or rotate the support 2 relative to the heads 4, 5, and vice versa. Preferably, the translation and / or rotation are performed in the plane extending from the support and / or in the plane coinciding with the support. This allows for the exchange of multiple optical lenses 3 resting on the support 2 by moving the support 2 relative to the optical heads 4, 5 (and vice versa), thereby enabling continuous measurements of the multiple optical lenses 3.

[0271] In this case, according to the first variant, the measuring device 1 is also arranged to perform the step of collecting at least two reflected beams 412, 512 for the support 2 relative to multiple relative positions of the two optical heads 4, 5.

[0272] In this case, according to the second variant, the measuring device 1 is also arranged to perform the step of collecting at least two reflected beams 412, 512 and at least one transmitted beam 413, 513 for the support 2 at multiple relative positions to the two optical heads 4, 5.

[0273] According to this improvement, the measuring device 1 is also arranged to collect at least two reflected beams 412, 512 and / or at least one transmitted beam 413, 513 at the following locations:

[0274] - The relative positions of the support member 2 and the optical heads 4 and 5 such that the optical axes 41 and 51 of the optical heads 4 and 5 coincide with the optical axis of the optical lens 3 are called the center positions.

[0275] - The support 2 and the optical heads 4 and 5 are positioned such that the intersection of the optical axes 41 and 51 of the optical heads 4 and 5 with the lens 3 is located at at least one relative position in the annular peripheral region 9 of the lens 3, referred to as the assembly region 9, and / or

[0276] - The support 2 and the optical heads 4 and 5 are arranged such that the intersection of the optical axes 41 and 51 of the optical heads 4 and 5 with the optical lens 3 is located at at least one relative position between the assembly area 9 and the center position.

[0277] According to this improvement, the processing unit 6 is arranged and / or programmed and / or configured to calculate at least two thickness values ​​d3 of the optical lens 3 at at least two relative positions. lent To determine the geometry of optical lens 3.

[0278] According to this improvement, the processing unit 6 is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens 3 based on at least two group refractive index values ​​of the optical lens 3 calculated at at least two relative positions. lent The gradient. The distance between two relative positions can be used to divide by the difference between at least two calculated group refractive index values.

[0279] The group refractive index n of optical lens 3 lent The gradient with respect to displacement consists of the sum of two partial derivatives, each with respect to a different displacement direction. Thus, the group refractive index n of optical lens 3... lent The gradient is independent of the choice of the displacement distance used to measure it.

[0280] Of course, the present invention is not limited to the examples just described, and many modifications can be made to these examples without departing from the scope of the present invention.

[0281] Thus, variations of the previously disclosed embodiments can be combined with each other.

[0282] Furthermore, the various features, forms, variations, and embodiments of the present invention can be combined with each other in various ways, as long as they are not mutually exclusive or incompatible.

Claims

1. A group refractive index (n) of an optical lens (3) for non-contact measurement lent (1) A measuring device for measuring ( ) and / or geometric parameters and / or optical properties, the measuring device comprising: - Support (2), which is used to receive samples (3, 7). - Two optical heads (4, 5) are arranged on opposite sides of the support at a known distance from each other, such that the optical axis (41) of one optical head substantially coincides with the optical axis (51) of the other optical head. Each optical head is capable of guiding an incident light beam (411, 511), and each optical head is capable of collecting at least one light beam (412, 512) reflected from one of the surfaces (31, 32) of an optical lens intended to rest on the support, and at least one light beam reflected from the other surface of the optical lens intended to rest on the support. - An optical system (8), coupled to the optical head, is arranged as follows: • Emit one or more light beams, which propagate to one or each of the optical heads. • Detect and analyze at least two light beams reflected by the optical lens and collected by one or more optical heads using interferometry. - A processing unit (6) is arranged and / or programmed and / or configured to determine the group refractive index of the optical lens and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens, based on calibration data of the measuring device, based on one or more emitted light beams and based on the at least two light beams reflected by the optical lens and collected by the one or more optical heads.

2. The measuring device (1) according to claim 1, wherein, The at least two light beams (412, 512) reflected by the optical lens (3) and collected by the one or more optical heads (4, 5) include at least one light beam collected by one of the optical heads and reflected by a surface (31, 32) of the optical lens facing another positioned in the optical head, wherein the processing unit (6) is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens based on the at least two light beams (412, 512) reflected by the optical lens (3) and collected by the one or more optical heads (4, 5). lent And / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

3. The measuring device (1) according to claim 1 or 2, wherein, The at least two light beams (412, 512) reflected by the optical lens (3) and collected by the one or more optical heads (4, 5) include at least one light beam reflected by a given surface (31, 32) of the optical lens and collected by an optical head facing the given surface of the optical lens, and at least one light beam reflected by a surface of the optical lens opposite to the given surface and collected by an optical head facing the opposite surface of the optical lens, wherein the processing unit (6) is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens based on the at least two light beams (412, 512) reflected by the optical lens (3) and collected by the one or more optical heads (4, 5). lent And / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

4. The measuring device (1) according to any one of the preceding claims, wherein: - One or each of the optical heads (4, 5) is also capable of collecting at least one beam of light (413, 513) that has been transmitted through the optical lens (3) intended to rest on the support (2). - The optical system (8) is arranged to also detect at least one light beam that has passed through the optical lens and is collected by one of the optical heads. - The processing unit (6) is arranged and / or programmed and / or configured to also determine the group refractive index n of the optical lens (3) based on at least one beam transmitted through the lens and collected by one of the optical heads. lent And / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

5. The measuring device (1) according to any one of the preceding claims, comprising means for moving the support (2) and the two optical heads (4, 5) relative to each other.

6. The measuring device (1) according to the preceding claim in conjunction with claim 3, wherein, The means for relative motion is arranged to generate relative motion between the support (2) and the optical heads (4, 5) by translation and / or rotation; the measuring device is arranged to perform the following steps: collecting at least two reflected beams (412, 512) and / or at least one transmitted beam (413, 513) for multiple relative positions of the support relative to the two optical heads.

7. A group refractive index (n) of an optical lens (3) for non-contact measurement lent A method for measuring ( ) and / or geometric parameters and / or optical properties, said measurement method comprising the following steps: - One or more light beams are emitted by the optical system (8) of the measuring device (1), and the emitted light beams or each emitted light beam propagates to discrete optical heads (4, 5), each of which is arranged to guide the incident light beam (411, 511). The two optical heads are arranged on both sides of the support (2) at a known distance from each other, such that the optical axis (41) of one of the optical heads is substantially coincident with the optical axis (51) of the other optical head. The samples (3, 7) are arranged on the support. - Detect at least two light beams (412, 512) reflected by the optical lenses and collected by one or more optical heads through the optical system. - The processing unit (6) determines the group refractive index (n) of the optical lens based on one or more emitted light beams and at least two light beams reflected by the optical lens and collected by the one or more optical heads. lent And / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens, wherein the at least one parameter related to the geometry of the optical lens is, for example, the thickness of the optical lens (d3). lent The at least one parameter related to the optical properties of the optical lens, such as the optical path length (E) separating the two surfaces of the optical lens, is mentioned. lent ).

8. The method according to the preceding claim, wherein, The at least two light beams (412, 512) reflected by the optical lens (3) and collected by the one or more optical heads (4, 5) include: - At least one light beam reflected by a given surface (31, 32) of the optical lens and collected by an optical head facing the given surface of the optical lens, and at least one light beam reflected by a surface of the optical lens opposite to the given surface and collected by an optical head facing the opposite surface of the optical lens, and / or - At least one light beam reflected by a surface of an optical lens positioned in one of the optical heads and collected by another in the optical head. The processing unit (6) is arranged and / or programmed and / or configured to determine the group refractive index n of the optical lens based on the at least two beams (412, 512) reflected by the optical lens (3) and collected by the one or more optical heads (4, 5). lent And / or the refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens.

9. The method according to the preceding claim, wherein, The determination step includes one or more linear combinations of the at least two reflected beams (412, 512).

10. The method according to claim 8 or 9, wherein, Determine the group refractive index n of the optical lens. lent The steps of and / or the group refractive index gradient within the optical lens and / or the at least one parameter related to the geometry of the optical lens and / or the at least one parameter related to the optical properties of the optical lens are performed according to the following, wherein the at least one parameter related to the geometry of the optical lens is, for example, the thickness d3 of the optical lens. lent The at least one parameter related to the optical properties of the optical lens, such as the optical path E separating the two surfaces of the optical lens. lent The following items are from: - Optical distance Z4 lent31 and Z5 lent32 For each corresponding optical head, the optical distance Z4 lent31 and Z5 lent32 The sum of the optical distances traveled by the incident light beams (411, 511) from the given optical head (4, 5) to the surface of the optical lens facing the given optical head, and the optical distances traveled by the reflected light beams (412, 512) from the surface of the optical lens facing the given optical head to the given optical head, and - Optical distance Z4 lent32 and Z5 lent31 For each corresponding optical head, the optical distance Z4 lent32 and Z5 lent31 The sum of the optical distance traveled by the incident beam from the given optical head to the surface of the optical lens opposite to the given optical head, and the optical distance traveled by the reflected beam from the surface of the optical lens opposite to the given optical head to the given optical head.

11. The method according to claim 10, wherein, The determining step includes calculating the optical path E of the two surfaces (31, 32) separating the optical lens (3) according to Equation 1. lent : Equation 1 Where ΔZ1 equals Z4 lent32 -Z4 lent31 ΔZ2 equals Z5 lent31 -Z5 lent32 , a and b are real numbers, and E lent(re) The optical path E is the distance between the two surfaces of the optical lens. lent E lent(re) Determined based on the at least two reflected beams (412, 512).

12. The method according to claim 10 or 11, wherein, The determining step includes calculating the optical path length Elent of the two surfaces (31, 32) separating the optical lens (3) according to Equation 2: Equation 2 Where ∑ZX is different from ∑ZY, and ∑ZX and ∑ZY are equal to ∑Z1, ∑Z2, ∑Z2' or ∑Z3. ∑Z1 equals Z5 lent32 +Z4 lent31 , ∑Z2 equals Z4 lent31 +Z5 lent31 And ∑Z2' equals Z4 lent32 +Z5 lent32 , ∑Z3 equals Z5 lent31 +Z4 lent32 , e and f are real numbers, and E lent(re) The optical path E is the distance between the two surfaces of the optical lens. lent E lent(re) Determined based on the at least two reflected beams (412, 512).

13. The method according to the preceding claim, wherein, The determining step includes calculating the thickness d3 of the optical lens (3) according to Equation 3. lent : Equation 3 Where u, v, w, x, and y are integers, rational numbers, or real numbers, and u + v + w + x = 1, and I is calibration data or known data. C is the calibration data, and d3 lent(re) The thickness of the optical lens is determined based on the at least two reflected beams (412, 512).

14. The method according to any one of claims 7 to 13, wherein: - The detection step also includes detecting at least one light beam (413, 513) that has been transmitted through an optical lens (3) placed on the support (2) and collected by one of the optical heads (4, 5). The determination step is also based on the at least one beam of light that has passed through the optical lens and is collected by one of the optical heads.

15. The method according to the preceding claim, wherein, The determination step includes one or more linear combinations of the at least two reflected beams (412, 512) and the at least one transmitted beam (413, 513).

16. The method according to the preceding claim, wherein, Determine the group refractive index n of the optical lens. lent The steps of and / or the group refractive index gradient within the optical lens and / or at least one parameter related to the geometry of the optical lens and / or at least one parameter related to the optical properties of the optical lens are also implemented based on the optical distance traveled by the incident beam (411, 511) from one optical head (4, 5) through the sample (3) to another optical head, wherein the at least one parameter related to the geometry of the optical lens is, for example, the thickness d3 of the optical lens. lent The at least one parameter related to the optical properties of the optical lens, such as the optical path E separating the two surfaces of the optical lens. lent .

17. The method according to the preceding claim, wherein, The determination step includes calculating the optical path E separating the two surfaces of the optical lens according to Equation 4. lent and / or the thickness d3 of the optical lens (3) lent : Equation 4 ZT4 and ZT5 represent the optical distances traveled by the incident light beam (411, 511) from one of the optical heads (4, 5) through the sample to the other optical head (5, 4), and vice versa. σ, p, q, r, and s are real numbers. D and D' are calibration data. for , for , d3 lent(tr) Specifically, the thickness d3 of the optical lens is determined based on the at least one transmitted beam. lent ,and E lent(tr) Specifically, the optical path E separating the two surfaces of the optical lens is determined based on the at least one transmitted beam. lent .

18. The method according to any one of claims 7 to 17, wherein, The determining step includes calculating the group refractive index n of the optical lens (3) according to Equation 5. lent : Equation 5.

19. The measurement method according to any one of claims 9 to 13, or the measurement method according to any one of claims 15 to 18 in combination with any one of claims 9 to 13, wherein, The optical distance is determined by optical coherence tomography (OCT).

20. The method according to any one of claims 7 to 19, comprising the step of generating relative translational and / or rotational motions of the support (2) and the optical heads (4, 5) relative to each other by means of means for relative motion.

21. The method according to the preceding claim, comprising collecting the at least two reflected beams (412, 512) and / or the at least one transmitted beam (413, 513) at the following locations: - The relative position of the support (2) and the optical head (4, 5) such that the optical axis (41, 51) of the optical head coincides with the optical axis of the optical lens (3) is called the center position, and - At least one of the support member and the optical head is such that the intersection of the optical axis of the optical head and the lens is located in a relative position within the annular peripheral region (9) of the lens, referred to as the assembly region (9), and / or - At least one of the support member and the optical head is such that the intersection of the optical axis of the optical head and the lens is located at a relative position between the assembly area and the center position.

22. The method according to the preceding claim, further comprising at least two thickness values ​​d3 of the optical lens calculated at at least two relative positions. lent and / or at least two optical paths E lent To determine the geometry of the optical lens (3).

23. The method according to claim 21 or 22, comprising determining the group refractive index n of the optical lens (3) based on at least two group refractive index values ​​of the optical lens calculated at at least two relative positions. lent The gradient.

Images