Tiny pattern projector

Abstract

An apparatus for intraoral scanning includes an elongated wand including a probe at a distal end of the elongated wand. The device further comprises one or more structured light projectors disposed within the probe, each structured light projector comprising: (a) a housing; (b) a light source disposed within the housing and including a semiconductor laser core and a beam shaping optical element; and (c) a pattern generating optical element. The distance D between the emission point of the semiconductor laser core and the input surface of the beam shaping optical element is 50-250 microns. Each structured light projector is configured to project a light pattern onto the mouth inner surface when a light source of the structured light projector is actuated to emit light through a pattern generating optical element of the structured light projector.

Description

Technical Field

[0001] The present invention relates generally to three-dimensional imaging, and more particularly to intra-oral three-dimensional imaging using structured light illumination. Background Art

[0002] Dental impressions of the three-dimensional surfaces of a subject's mouth (e.g., teeth and gums) are used to plan dental procedures. Conventional dental impressions are made using a dental impression tray filled with an impression material (e.g., PVS or alginate) into which the subject bites. The impression material then cures into a negative impression of the teeth and gums, from which a three-dimensional model of the teeth and gums can be formed.

[0003] Digital dental impressions utilize intraoral scanning to generate a three-dimensional digital model of the three-dimensional surfaces within a subject's mouth. Digital intraoral scanners typically use structured light three-dimensional imaging. The surfaces of a subject's teeth may be highly reflective and somewhat translucent, which may reduce the contrast in the structured light pattern reflected from the teeth. Therefore, in order to improve the capture of the intraoral scan, when using a digital intraoral scanner that utilizes structured light three-dimensional imaging, the subject's teeth may be coated with an opaque powder prior to scanning to facilitate obtaining a usable level of contrast in the structured light pattern, for example, to transform the surface into a scattering surface. Although some progress has been made in intraoral scanners that utilize structured light three-dimensional imaging, additional advantages may still be available.

[0004] International Patent Application No. PCT / US2019 / 038510 to Saphier et al. (published as WO2019 / 246542 to Saphier et al., assigned to the assignee of the present application, and incorporated herein by reference) describes a device for intraoral scanning comprising an elongated handheld wand having a probe. One or more light projectors and two or more cameras are disposed within the probe. Each light projector has a pattern generating optical element that can form a light pattern using diffraction or refraction. Each camera can be configured to focus between 1 mm and 30 mm from the lens farthest from the camera sensor. Other applications are also described.

[0005] International Patent Application No. PCT / US2020 / 039438 to Saphier et al. (published as WO2020 / 264035 to Saphier et al., assigned to the assignee of the present application, and incorporated herein by reference) describes a method for generating a 3D image, the method comprising driving a structured light projector to project a light pattern onto an intraoral 3D surface, and driving a camera to capture images, each image including at least a portion of the projected pattern, each camera including a pixel array. A processor compares a series of images captured by each camera and determines which portions of the projected pattern can be tracked on the image. The processor constructs a three-dimensional model of the intraoral three-dimensional surface based at least in part on the comparison of the series of images. Other embodiments are also described. Summary of the invention

[0006] Applications of the present invention include systems and methods related to a three-dimensional intraoral scanning device, which includes one or more cameras and one or more light projectors (e.g., structured light projectors). For example, certain applications of the present invention may be related to an intraoral scanning device having multiple cameras and multiple structured light projectors. For example, in some specific applications of the present invention, a device for intraoral scanning is provided, which includes an elongated handheld wand having a probe at the distal end of the handheld wand. Typically, one or more structured light projectors are disposed within the probe.

[0007] According to some applications of the present invention, each structured light projector includes a housing, in which a light source is disposed. In some embodiments, the housing is a sealed housing (e.g., hermetically sealed). Each light source includes at least one semiconductor laser core (semiconductor laser die) and at least one beam shaping optical element (beam shaping optical element). Typically, the semiconductor laser core and the beam shaping optical element are disposed in a common chamber of the housing. The inventors have recognized that placing the beam shaping optical element and the semiconductor laser core of the structured light projector in the same chamber of the housing enables the distance between the emission point of the semiconductor laser core and the input surface of the beam shaping optical element to be shorter than the distance allowed by conventional laser diodes. Typically, the distance D between the emission point of the semiconductor laser diode and the input surface of the beam shaping optical element is at least 50 microns and / or less than 250 microns. This in turn brings many advantages, which will be further described below. Some examples of the advantages provided by the application of the present invention are:

[0008] ● Overall reduction in the size of the structured light projector, which in turn can reduce the size of the probe and increase the flexibility of the placement of the structured light projector and camera,

[0009] ●Increase the collection efficiency of laser,

[0010] ●Increase the depth of focus of the structured light projector,

[0011] ● Using multiple laser cores within a single structured light projector to increase the amount of structured light features used for 3D reconstruction without increasing the size and / or number of structured light projectors, and

[0012] ● Reduce speckle noise when using multiple laser cores.

[0013] Each structured light projector includes at least one pattern generating optical element positioned such that when the light source of the structured light projector is actuated to emit light through the pattern generating optical element of the structured light projector, each structured light projector projects a light pattern onto the inner surface of the mouth.

[0014] Therefore, according to some applications of the present invention, a first device for intraoral scanning is provided, the first device comprising:

[0015] an elongated hand-held wand including a probe at a distal end of the hand-held wand; and

[0016] One or more structured light projectors are disposed in the probe, each structured light projector comprising:

[0017] (a) Housing;

[0018] (b) a light source, disposed in the housing and comprising:

[0019] Semiconductor laser cores; and

[0020] beam shaping optics; and

[0021] (c) pattern generating optical element,

[0022] in:

[0023] The distance D between the emission point of the semiconductor laser core and the input face of the beam shaping optical element is 50-250 microns, and

[0024] Each structured light projector is configured to project a light pattern onto an interior surface of the mouth when the light source of the structured light projector is actuated to emit light through the pattern generating optical element of the structured light projector.

[0025] For some applications, the housing is a sealed housing.

[0026] For some applications, the semiconductor laser core and the beam shaping optics are disposed within a housing (eg, within a sealed housing) which together with the distance D of 50-250 microns allows the longest dimension of the sealed housing to be 1.5-2.5 mm.

[0027] For some applications, the height of the housing is 1.6-2.4 mm.

[0028] For some applications, the beam shaping optical element is positioned within the housing such that at least 75% of the light emitted by the semiconductor laser core enters the beam shaping optical element.

[0029] For some applications, the beam shaping optics are positioned within the housing such that 80-90% of the light emitted by the semiconductor laser core enters the beam shaping optics.

[0030] For some applications, the housing includes metal, and the semiconductor laser core is disposed within the housing such that heat is conducted from the semiconductor laser core to the metal of the housing.

[0031] For some applications, the semiconductor laser core is mounted on a submount within a housing such that heat is conducted from the semiconductor laser core through the submount to the metal of the housing.

[0032] For some applications, the abutment is ceramic.

[0033] For some applications, the device also includes one or more cameras disposed within the probe, wherein a distance between (i) an optical axis of at least one camera and (ii) an optical axis of at least one structured light projector adjacent to the at least one camera is 3-5 mm.

[0034] For some applications, (a) the probe includes a transparent window through which one or more structured light projectors project light and through which one or more cameras receive light, and (b) the distance from the transparent window where 50% overlap of the respective fields of view of at least one camera and at least one adjacent structured light projector is 2-6 mm.

[0035] For some applications, (a) the probe includes a transparent window through which one or more structured light projectors project light and through which one or more cameras receive light, and (b) the distance from the transparent window where the corresponding fields of view of at least one camera and at least one adjacent structured light projector begin to overlap is 1-3 mm.

[0036] For some applications, the housing includes a transparent window through which the laser light exits the housing, and the transparent window includes the pattern generating optical element.

[0037] For some applications:

[0038] a. The angle between the optical axis of the beam shaping optic and the optical axis of the pattern generating optic is 65-120 degrees,

[0039] The apparatus also includes a reflector disposed within the housing and positioned to reflect laser light exiting the beam shaping optical element toward the pattern generating optical element.

[0040] For some applications, the pattern generating optics are disposed within the probe but outside the housing, and the distance traveled by the laser light from exiting the beam shaping optics to entering the pattern generating optics is 2-8 mm.

[0041] For some applications, the pattern generating optics are disposed within the probe but outside the housing, and the distance traveled by the laser light from exiting the beam shaping optics to entering the pattern generating optics is 8-25 mm.

[0042] For some applications:

[0043] a. The pattern generating optical element is disposed within the probe but outside the housing so that the angle between the optical axis of the beam shaping optical element and the optical axis of the pattern generating optical element is 50-100 degrees,

[0044] b. The device further comprises a reflector disposed within the probe and positioned to reflect the laser light leaving the beam shaping optical element toward the pattern generating optical element, and

[0045] c. The distance the laser travels from leaving the beam shaping optics to entering the pattern generating optics is 8-25 mm.

[0046] For some applications, for at least one of the one or more structured light projectors, the semiconductor laser core is a first semiconductor laser core and the light source also includes a second semiconductor laser core.

[0047] For some applications, the first semiconductor laser core and the second semiconductor laser core are mounted on a common submount within the housing.

[0048] For some applications, the first semiconductor laser core and the second semiconductor laser core have different wavelengths, and the device also includes a computer processor configured to actuate the first semiconductor laser core and the second semiconductor laser core so that at least one structured light projector projects a pattern at each of the two different wavelengths.

[0049] For some applications, the computer processor is configured to alternately actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector alternately projects a pattern at each of two different wavelengths.

[0050] For some applications, the computer processor is configured to simultaneously actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector simultaneously projects a pattern at each of the two different wavelengths.

[0051] For some applications, the beam shaping optical element is a first beam shaping optical element, and the light source further includes a second beam shaping optical element, the first beam shaping optical element and the second beam shaping optical element being arranged such that laser light from the first semiconductor laser core enters and then exits the first beam shaping optical element, and laser light from the second semiconductor laser core enters and then exits the second beam shaping optical element, and

[0052] a. The pattern generating optical element is a first pattern generating optical element, and at least one structured light projector also includes a second pattern generating optical element, and the first pattern generating optical element and the second pattern generating optical element are arranged so that the laser light leaving the first beam forming optical element enters the first pattern generating optical element, and the laser light leaving the second beam forming optical element enters the second pattern generating optical element.

[0053] For some applications, the first pattern generating optical element and the second pattern generating optical element project the same light pattern such that at least one structured light projector projects (a) a light pattern of a first wavelength in a first position onto the inner surface of the mouth, and projects (b) a light pattern of a second wavelength translationally shifted relative to the first position onto the inner surface of the mouth.

[0054] For some applications, the projected light pattern of the second wavelength is translationally displaced relative to the first position by a distance between optical axes of the first pattern generating optical element and the second pattern generating optical element.

[0055] For some applications, at least one structured light projector projects a first pattern from a first pattern generating optical element and projects a second pattern from a second pattern generating optical element, the first pattern being different from the second pattern.

[0056] For some applications, the first semiconductor laser core and the second semiconductor laser core are mounted within the housing such that the first semiconductor laser core and the second semiconductor laser core emit laser light in the same direction, and the first pattern generating optical element and the second pattern generating optical element are first and second regions, respectively, of a common lens.

[0057] For some applications, the first semiconductor laser core and the second semiconductor laser core are mounted within the housing such that the first semiconductor laser core and the second semiconductor laser core emit laser light in the same direction, and the first beam shaping optical element and the second beam shaping optical element are first and second regions, respectively, of a common lens.

[0058] For some applications, the first beam shaping optical element includes a first lens and the second beam shaping optical element includes a second lens, the first lens being separate from the second lens.

[0059] For some applications, the beam shaping optical element is arranged such that laser light from each of the first semiconductor laser core and the second semiconductor laser core (i) enters the beam shaping optical element along a different respective axis of the beam shaping optical element and (ii) subsequently impinges on the pattern generating optical element at a different respective angle such that the projected pattern for each wavelength is angularly shifted about the optical axis of the pattern generating optical element.

[0060] For some applications, the first semiconductor laser core and the second semiconductor laser core have the same wavelength, and

[0061] a. The apparatus further comprises a computer processor configured to alternately actuate the first semiconductor laser core and the second semiconductor laser core.

[0062] For some applications, the beam shaping optical element is a first beam shaping optical element, and the light source further includes a second beam shaping optical element, the first beam shaping optical element and the second beam shaping optical element being arranged such that laser light from the first semiconductor laser core enters and then exits the first beam shaping optical element, and laser light from the second semiconductor laser core enters and then exits the second beam shaping optical element, and

[0063] a. The pattern generating optical element is a first pattern generating optical element, and at least one structured light projector also includes a second pattern generating optical element, and the first pattern generating optical element and the second pattern generating optical element are arranged so that the laser light leaving the first beam forming optical element enters the first pattern generating optical element, and the laser light leaving the second beam forming optical element enters the second pattern generating optical element.

[0064] For some applications, the first pattern generating optical element and the second pattern generating optical element project the same light pattern such that at least one structured light projector alternately projects (a) a light pattern in a first position onto the inner surface of the mouth and (b) a light pattern translationally shifted relative to the first position onto the inner surface of the mouth.

[0065] For some applications, at least one structured light projector alternately projects a first pattern from a first pattern generating optical element and a second pattern from a second pattern generating optical element, the first pattern being different from the second pattern.

[0066] For some applications, the first semiconductor laser core and the second semiconductor laser core are mounted within the housing such that the first semiconductor laser core and the second semiconductor laser core emit laser light in the same direction, and the first pattern generating optical element and the second pattern generating optical element are first and second regions, respectively, of a common lens.

[0067] For some applications, the first semiconductor laser core and the second semiconductor laser core are mounted within the housing such that the first semiconductor laser core and the second semiconductor laser core emit laser light in the same direction, and the first beam shaping optical element and the second beam shaping optical element are first and second regions, respectively, of a common lens.

[0068] For some applications, the first beam shaping optical element includes a first lens and the second beam shaping optical element includes a second lens, the first lens being separate from the second lens.

[0069] For some applications:

[0070] a. The beam shaping optical element is arranged so that laser light from each of the first semiconductor laser core and the second semiconductor laser core (i) enters the beam shaping optical element along a different corresponding axis of the beam shaping optical element and (ii) subsequently impinges on the pattern generating optical element at a different corresponding angle so that at least one structured light projector projects a pattern that is alternately angularly shifted around the optical axis of the pattern generating optical element.

[0071] For some applications, for at least one of the one or more structured light projectors:

[0072] a. the semiconductor laser core is a first semiconductor laser core, and the light source further includes a second semiconductor laser core, the first semiconductor laser core and the second semiconductor laser core are mounted in the housing so that the first semiconductor laser core and the second semiconductor laser core emit laser light in respective first and second directions, the first direction being different from the second direction, and

[0073] b. The apparatus further comprises a computer processor configured to actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector projects a first pattern along a first direction and a second pattern along a second direction.

[0074] For some applications, the first semiconductor laser core and the second semiconductor laser core are mounted on a common submount within the housing.

[0075] For some applications:

[0076] a. the beam shaping optical element is a first beam shaping optical element, and the light source further comprises a second beam shaping optical element, the first beam shaping optical element and the second beam shaping optical element being arranged so that the laser light from the first semiconductor laser core enters and then leaves the first beam shaping optical element, and so that the laser light from the second semiconductor laser core enters and then leaves the second beam shaping optical element, and

[0077] b. The pattern generating optical element is a first pattern generating optical element, and at least one structured light projector also includes a second pattern generating optical element, and the first pattern generating optical element and the second pattern generating optical element are arranged so that the laser light leaving the first beam forming optical element enters the first pattern generating optical element, and the laser light leaving the second beam forming optical element enters the second pattern generating optical element.

[0078] For some applications, the first semiconductor laser core and the second semiconductor laser core have the same wavelength.

[0079] For some applications, the first semiconductor laser core and the second semiconductor laser core have different wavelengths.

[0080] For some applications, the first direction and the second direction are opposite to each other.

[0081] For some applications, the computer processor is configured to actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector alternately projects a first pattern along a first direction and a second pattern along a second direction.

[0082] For some applications, the computer processor is configured to actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector simultaneously projects a first pattern in a first direction and a second pattern in a second direction.

[0083] For some applications, for at least one of the one or more structured light projectors:

[0084] a. the pattern generating optical element is a first pattern generating optical element, and at least one structured light projector further comprises a second pattern generating optical element,

[0085] b. the first pattern generating optical element and the second pattern generating optical element are two corresponding areas on a common substrate, the common substrate comprising a beam splitter and a reflector disposed within the common substrate, and

[0086] c. The apparatus further comprises a computer processor configured to actuate the semiconductor laser core such that:

[0087] d. The laser light leaving the light source is split into a first beam and a second beam by a beam splitter in the substrate, and

[0088] e. The first light beam enters the first pattern generating optical element, and the second light beam is reflected by the reflector towards the second pattern generating optical element to produce two separate projected patterns that are translationally shifted relative to each other.

[0089] For some applications, a first light beam enters a first pattern generating optical element and a second light beam is reflected by a reflector toward a second pattern generating optical element to produce two separate projection patterns that are shifted relative to each other by a distance between optical axes of the first pattern generating optical element and the second pattern generating optical element.

[0090] According to some applications of the present invention, a second device for intraoral scanning is also provided, the second device comprising:

[0091] an elongated hand-held wand including a probe at a distal end of the hand-held wand; and

[0092] One or more structured light projectors are disposed in the probe, each structured light projector comprising:

[0093] (a) Housing;

[0094] (b) a light source, disposed in the housing and comprising:

[0095] Semiconductor laser cores; and

[0096] beam shaping optics; and

[0097] (c) pattern generating optical element,

[0098] in:

[0099] The semiconductor laser core and the beam shaping optical element are disposed in a common cavity of the housing, and

[0100] Each structured light projector is configured to project a light pattern onto an interior surface of the mouth when the light source of the structured light projector is actuated to emit light through the pattern generating optical element of the structured light projector.

[0101] It should be noted that all the above-mentioned applications of the first device can be executed with the second device mutatis mutandis.

[0102] The present invention will be more fully understood through the following detailed description of the application of the present invention in conjunction with the accompanying drawings, in which: BRIEF DESCRIPTION OF THE DRAWINGS

[0103] Figure 1 is a schematic diagram of an elongated handheld wand for intraoral scanning according to some applications of the present invention;

[0104] Figure 2A-2C are schematic diagrams of a top view and two side views of a structured light projector according to some applications of the present invention;

[0105] Figure 3 is a schematic diagram of a probe of an elongated handheld wand according to some applications of the present invention, showing an example configuration for positioning a plurality of structured light projectors and a plurality of cameras within the probe;

[0106] Figure 4 is a schematic diagram of a probe according to some applications of the present invention, which shows a structured light projector disposed in the probe and a camera disposed in the probe;

[0107] Figure 5A-Figure 5B is a schematic diagram of a structured light projector and a beam shaping optical element according to some applications of the present invention;

[0108] Fig. 6A is a schematic diagram of the relative positioning of a semiconductor laser core and a beam shaping optical element of a structured light projector according to some applications of the present invention;

[0109] Figure 6B shows the depth of focus when utilizing a larger focusing lens aperture;

[0110] Figure 7 is a schematic diagram of a structured light projector according to some applications of the present invention;

[0111] Figure 8 is a schematic diagram of a structured light projector disposed in a probe according to some applications of the present invention;

[0112] Fig. 9 is a schematic diagram of a structured light projector disposed in a probe according to some applications of the present invention;

[0113] Fig.10 is a schematic diagram of a structured light projector disposed in a probe according to some applications of the present invention;

[0114] Figure 11-Figure 16 is a schematic diagram of a structured light projector having a light source including a first semiconductor laser core and a second semiconductor laser core according to some applications of the present invention; and

[0115] Fig.17 is a schematic diagram of a structured light projector having a single semiconductor laser core and split pattern generating optical elements according to some applications of the present invention. DETAILED DESCRIPTION

[0116] Reference now Figure 1, which is a schematic diagram of an elongated handheld wand 20 for intraoral scanning according to some applications of the present invention. For some applications, the elongated handheld wand 20 has a probe 24 located at a distal end 26 of the handheld wand 20. One or more structured light projectors 22 are disposed within the probe 24. It should be noted that by way of example and not limitation, Figure 1 Three structured light projectors 22 are shown in A, and the scope of the present invention includes one or more structured light projectors 22 disposed within the probe 24. In some applications, during intraoral scanning, the probe 24 enters the oral cavity of a subject to scan the intraoral surface 28.

[0117] Reference now Figure 2A-2C , which are schematic diagrams of a top view and two side views of a structured light projector 22 according to some applications of the present invention, respectively. Each structured light projector 22 has a housing 30, for example a sealed housing, such as an airtight sealed housing, and a light source 32 disposed within the sealed housing 30. In some embodiments, the sealed housing has an airtight seal. In some embodiments, the sealed housing does not have an airtight seal, but has a seal that prevents liquid molecules from flowing in. In some embodiments, the sealed housing is sealed against moisture and protects the laser core of the structured light projector 22 from moisture. The following discusses embodiments with reference to sealed housings. However, it should be understood that embodiments may also include non-sealed housings. Any discussion with reference to sealed housings also applies to embodiments in which the housing is not sealed.

[0118] The light source 32 includes a semiconductor laser core 34 and a beam shaping optical element 36. The semiconductor laser core 34 and the beam shaping optical element 36 are typically disposed in a common chamber 40 of the sealed housing 30 such that they are exposed to the same gas environment, i.e., there is fluid communication between the semiconductor laser core 34 and the beam shaping optical element 36. Positioning the beam shaping optical element 36 and the semiconductor laser core 34 in the same chamber 40 allows the distance D between the emission point 42 of the semiconductor laser core 34 and the input face 44 of the beam shaping optical element 36 to be smaller than that allowed by conventional laser diodes (in which the beam shaping lens is positioned outside the hermetically sealed housing of the diode). For some applications, the distance D is at least 50 microns and / or less than 250 microns. For some applications, (i) both the semiconductor laser core 34 and the beam shaping optical element 36 are disposed within the sealed housing 30, and (ii) the distance D of at least 50 microns and / or less than 250 microns together allows the longest dimension L1 of the sealed housing 30 (e.g., Figure 2C For some applications, the height H1 of the sealing housing 30 (as shown) is at least 1.5 mm and / or less than 2.5 mm. Figure 2CFor some applications, the sealed housing 30 is cylindrical, and the height H1 is the diameter of the cylinder. For some applications, the sealed housing 30 is shaped as a prism, such as a rectangular prism.

[0119] Each structured light projector 22 also includes a pattern generating optical element 38, such as a diffractive optical element (DOE) or a refractive optical element. When the light source 32 of the structured light projector 22 is actuated to emit light 39 through the pattern generating optical element 38 of the structured light projector 22, each structured light projector 22 projects a light pattern onto the inner surface 28 of the mouth. For some applications, the pattern generating optical element 38 is disposed within the probe 24, but outside the sealed housing 30 of the structured light projector 22, such as Figure 2A-2B shown.

[0120] Reference now Figure 3 , which is a schematic diagram of a probe 24 according to some applications of the present invention, showing an example configuration for positioning multiple structured light projectors 22 and multiple cameras 46 within the probe 24. A broad spectrum LED 48, such as a white light LED or a near infrared (NIR) LED, is also shown. The above-described small size of the sealed housing 30 including the beam shaping optical element 36 disposed within the sealed housing 30 allows for an overall reduction in the size of the probe 24. Generally, the reduction in the size of the probe 24 corresponds to a reduction in the size of the elements disposed within the probe 24, that is, the small size of the structured light projectors 22 of these applications of the present invention allows for a reduction in the size of the probe 24. Reducing the size of the probe 24 can provide a more comfortable patient experience during intraoral scanning using the slender handheld wand 20. For some applications, the height H2 of the probe 24 (in Figure 1 ) is at least 10 mm and / or less than 15 mm, and the width W of the probe 24 (in Figure 3 ) is at least 12 mm and / or less than 18 mm, and the length L3 of the probe 24 (shown in Figure 3 ) is at least 10 mm and / or less than 30 mm. Typically, the ratio of width W to height H2 is at least 0.8 and / or less than 2.5. It should be noted that Figure 3 The specific configuration shown in Figure 3 The specific numbers of structured light projectors 22 , cameras 46 , and broad-spectrum LEDs 48 shown in FIG. 4 are exemplary only and are not intended to be limiting.

[0121] Reference now Figure 4, which is a schematic diagram of a probe 24 according to some applications of the present invention, showing a structured light projector 22 disposed within the probe 24 and a camera 46 disposed within the probe 24. For some applications, one or more cameras 46 are disposed within the probe 24. Typically, the probe 24 has a transparent window 50 through which the one or more structured light projectors 22 project light and through which the one or more cameras 46 receive light. The above-mentioned small size of the sealed housing 30 of the structured light projector 22 enables the structured light projector 22 to be positioned in close proximity to an adjacent camera 46. For example, in some applications, a distance D2 between (i) an optical axis 52 of at least one camera 46 and (ii) an optical axis 54 of at least one structured light projector 22 adjacent to the at least one camera 46 is at least 3 mm and / or less than 5 mm.

[0122] The close proximity between the camera 46 and the adjacent structured light projector 22 causes the respective fields of view 56 and 58 of the camera 46 and the adjacent structured light projector 22 to overlap each other at a relatively close distance from the transparent window 50. For some applications, the distance D3 from the transparent window 50 at which 50% of the respective fields of view 56 and 58 of at least one camera 46 and at least one adjacent structured light projector 22 overlap is at least 2 mm and / or less than 6 mm. For some applications, the distance D4 from the transparent window 50 at which the respective fields of view 56 and 58 of at least one camera 46 and at least one adjacent structured light projector 22 begin to overlap is at least 1 mm and / or less than 3 mm.

[0123] Reference now Figure 5A-Figure 5B , which is a schematic diagram of a structured light projector 22 and a beam shaping optical element 36 according to some applications of the present invention. Typically, the sealed housing 30 is made of metal, and the semiconductor laser core 34 is disposed within the sealed housing 30 such that heat is conducted from the semiconductor laser core 34 to the metal of the sealed housing 30. For some applications, the semiconductor laser core 34 is mounted on a base 60 within the sealed housing 30 such that heat is conducted from the semiconductor laser core 34 to the metal of the sealed housing 30 through the base 60, i.e., the base 60 serves as a heat sink for the semiconductor laser core 34. The base 60 is typically made of a material having high thermal conductivity, such as ceramic. The base 60 can also be positioned to serve as a base for the semiconductor laser core 34 such that the emission point 42 of the semiconductor laser core is aligned with the optical axis 62 of the beam shaping optical element 36 (e.g., Figure 2B For some applications, length L2 of platform 60 is at least 0.8 mm and / or less than 1.6 mm.

[0124] The beam shaping optical element 36 is typically a collimating lens (or a combination of collimating lenses) placed in the emission path of the semiconductor laser core 34 to change the shape of the naturally elliptical laser beam into a circular beam. Figure 5A The beam shaping optical element 36 is shown as a series of two cylindrical lenses, one of which is a fast axis collimating (FAC) lens 64 and the other is a slow axis collimating (SAC) lens 66. For some applications, the FAC lens 66 and the SAC lens 64 are two opposing surfaces of a single lens, such as Figure 5B For some applications, a combination of a cylindrical lens and a spherical lens may be used for the beam shaping optical element 36 (configuration not shown).

[0125] Reference now Fig. 6A , which is a schematic diagram of the relative positioning of a semiconductor laser core 34 and a beam shaping optical element 36 according to some applications of the present invention. Typically, the laser beam leaving the beam shaping optical element 36 is a Gaussian beam that converges at a certain focal distance D5 away from the beam shaping optical element 36. For a Gaussian beam that (i) has a given divergence angle θ (theta) and (ii) is focused at a given focal distance D5 by the beam shaping optical element, the depth of focus (i.e., the distance over which the Gaussian beam remains focused) increases as the distance between the emission point and the beam shaping optical element decreases.

[0126] As mentioned above Figure 2A-2C As described, placing the beam shaping optical element 36 together with the semiconductor laser core 34 in the sealed housing 30 enables the beam shaping optical element 36 to be positioned so that the distance D between the emission point 42 of the semiconductor laser core 34 and the input surface 44 of the beam shaping optical element 36 is very short, for example, at least 50 microns and / or less than 250 microns.

[0127] Fig. 6A 4 shows the distance D between the emission point 42 and the input face 44, and the divergence and subsequent convergence of a Gaussian laser beam 68 emitted from the semiconductor laser core 34 and having a divergence angle θ. In general, when focusing a Gaussian beam, for a given focal length, reducing the size of the focusing lens aperture increases the focal depth of the converging laser beam. For a given focal length D5, at Fig. 6A The depth of focus D6 is shown in FIG. Figure 6B6 shows how the depth of focus will be shorter than D6 for a Gaussian beam that: (i) has the same divergence angle as Gaussian beam 68, (ii) is focused at the same focal length as Gaussian beam 68, but (iii) utilizes a larger focusing lens aperture due to the greater distance between the emission point of the laser and the focusing lens causing the laser beam to be more divergent when entering the focusing lens. The close placement of the beam shaping optical element 36 and the emission point 42 of the semiconductor laser core 34 enables the laser beam 68 to enter the beam shaping optical element 36 while the laser beam 68 remains narrow, effectively creating a narrow aperture.

[0128] It is known in the art of photography that reducing the size of the aperture increases the depth of focus. In some prior art optical systems utilizing lasers, a beam narrowing aperture may be placed between the laser and the focusing lens to reduce the size of the beam. The inventors have recognized that placing the beam shaping optical element 36 in close proximity to the emission point 42 of the semiconductor laser core 34 (as described above) effectively creates a small aperture, resulting in a desired depth of focus D6, without physically blocking a portion of the laser light from entering the beam shaping optical element 36. Thus, for some applications, at least 75% (e.g., at least 80% and / or less than 90%) of the light emitted by the semiconductor laser core 34 enters the beam shaping optical element 36. This high collection efficiency of the structured light projector 22, in turn, reduces heat buildup within the sealed housing 30, thereby extending the life of the structured light projector 22. Additionally, the higher collection efficiency of the structured light projector 22 enables the structured light projector 22 to be actuated at a lower pulse duty cycle (e.g., a pulse duty cycle of at least 5% and / or less than 25%), thereby generating an increased number of structured light pattern elements projected onto the inner surface 28 of the mouth per second.

[0129] Reference now Figure 7 , which is a schematic diagram of a structured light projector 22 according to some applications of the present invention. The sealed housing 30 includes a transparent window 70, through which the laser light 39 emitted from the semiconductor laser core 34 leaves the sealed housing 30. For some applications, the transparent window 70 includes the pattern generating optical element 38, that is, the pattern generating optical element 38 is a region of the transparent window 70 of the sealed housing 30.

[0130] Reference now Figure 8 , which is a schematic diagram of a structured light projector 22 provided with an angled tip 76 of the probe 24 according to some applications of the present invention. For some applications, the angle α (alpha) between the optical axis 62 of the beam shaping optical element 36 and the optical axis 72 of the pattern generating optical element 38 is at least 65 degrees and / or less than 120 degrees. Figure 8A specific example is shown where the angle α is 90 degrees and the pattern generating optical element 38 itself is a transparent window 70 of the sealed housing 30. The structured light projector 22 includes a reflector 74 disposed within the sealed housing 30 and positioned to reflect the laser light 39 exiting the beam shaping optical element 36 toward the pattern generating optical element 38. For some applications, positioning the pattern generating optical element 38 such that there is an angle α between the optical axes 62 and 72 can more efficiently use the space within the probe 24. For example, Figure 8 As shown, the use of the fold mirror 74 and the angle α between the optical axes 62 and 72 allows the sealed housing 30 of the structured light projector 22 to be placed into a tight space, such as the angled tip 76 of the probe 24, resulting in a very small distance D7 between the optical axis 72 of the pattern generating optical element 38 and the farthest point 78 of the tip 76. For some applications, the distance D7 is at least 0.5 mm and / or less than 3 mm.

[0131] Reference now Fig. 9 , which is a schematic diagram of a structured light projector 22 disposed within a probe 24 according to some applications of the present invention. Figure 2A-2C As described above, placing the beam shaping optical element 36 together with the semiconductor laser core 34 in the sealed housing 30 enables the beam shaping optical element 36 to be positioned so that the distance D between the emission point 42 of the semiconductor laser core 34 and the input face 44 of the beam shaping optical element 36 is very short, for example, at least 50 microns and / or less than 250 microns, thereby enabling the overall size of the structured light projector 22 to be reduced. The smaller size of the structured light projector 22, in turn, allows the space within the probe 24 to allow the pattern generating optical element 38 to be positioned further away from the beam shaping optical element 36. For some applications, the pattern generating optical element 38 is disposed within the probe 24 and outside the sealed housing 30, so that the distance D8 traveled by the laser light 39 from leaving the beam shaping optical element 36 to entering the pattern generating optical element 38 is at least 2 mm, for example at least 8 mm, and / or less than 25 mm from the transparent window 70 of the sealed housing 30. Fig. 9 An example is shown in which the pattern generating optical element is disposed at the transparent window 50 of the probe 24 and the sealed housing 30 is disposed within the probe 24 such that the output face 80 of the beam shaping optical element 36 is a distance D8 from the transparent window 50 of the probe 24 .

[0132] Typically, the laser beam exiting the beam shaping optical element 36 is a Gaussian beam that converges at a certain focal distance away from the beam shaping optical element 36. For a Gaussian beam that (i) has a given divergence angle, and (ii) is focused by a beam shaping optical element of a given aperture size, as the focal length of the Gaussian beam increases, the depth of focus (i.e., the distance over which the Gaussian beam remains focused) increases. The inventors have recognized that increasing the distance between the beam shaping optical element 36 and the pattern generating optical element 38 increases the focal length of the laser light 39, thereby increasing the depth of focus.

[0133] Reference now Fig.10 , which is a schematic diagram of a structured light projector 22 disposed within a probe 24 according to some applications of the present invention. For some applications, a pattern generating optical element 38 is disposed within the probe 24 but outside the sealed housing 30 such that an angle β (beta) between an optical axis 62 of the beam shaping optical element 36 and an optical axis 72 of the pattern generating optical element 38 is at least 50 degrees and / or less than 100 degrees. A folding mirror 82 is disposed within the probe 24 and positioned to reflect laser light 39 exiting the beam shaping optical element 36 toward the pattern generating optical element 38. The total distance D9+D10 traveled by the laser light 39 from exiting the beam shaping optical element 36 to entering the pattern generating optical element 38 is at least 8 mm and / or less than 25 mm.

[0134] Reference now Figure 11-Figure 16 , which is a schematic diagram of a structured light projector 22 having a light source 32 according to some applications of the present invention, the light source including a first semiconductor laser core 84 and a second semiconductor laser core 86, both of which are disposed within a sealed housing 30 of the structured light projector 22. The inventors have recognized that by installing more than one semiconductor laser core within the sealed housing 30, the number of structured light projectors within the probe 24 is effectively increased without occupying further space within the probe 24. Additional benefits of installing multiple laser cores within the sealed housing 30 are described below in conjunction with specific examples. For some applications of at least one structured light projector 22, the light source 32 includes a first semiconductor laser core 84 and a second semiconductor laser core 86. For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 are mounted to a common base 60 within the sealed housing 30, such as Figure 11-Figure 16 shown.

[0135] Now specific reference Figure 11-Figure 12 For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 have different wavelengths, that is, they project laser light of different colors. For example, the first semiconductor laser core 84 may be a blue laser and the second semiconductor laser core 86 may be a green laser. The computer processor 88 ( Figure 1) actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 so that the structured light projector 22 projects a pattern P of each of two different wavelengths.

[0136] Now specific reference Fig.11 . For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 each have their own respective beam shaping optical elements and pattern generating optical elements. That is, the laser light 85 from the first semiconductor laser core 84 enters and then exits the first beam shaping optical element 90, and the laser light 87 from the second semiconductor laser core 86 enters and then exits the second beam shaping optical element 92. The first beam shaping optical element 90 and the second beam shaping optical element 92 generally have the same characteristics as the beam shaping optical element 36 described above. The first pattern generating optical element 94 and the second pattern generating optical element 96 are arranged so that the laser light 85 exiting the first beam shaping optical element 90 enters the first pattern generating optical element 94, and the laser light 87 exiting the second beam shaping optical element 92 enters the second pattern generating optical element 96. It should be noted that the distance D between the emission point 42 of the semiconductor laser core 34 and the input face 44 of the beam shaping optical element 36 described above applies mutatis mutandis to the first beam shaping optical element 90 and the second beam shaping optical element 92.

[0137] For some applications, the first pattern generating optical element 94 and the second pattern generating optical element 96 project the same light pattern P, so that the structured light projector 22 projects (a) a first wavelength light pattern P in a first position onto the inner surface 28 of the mouth, and (b) a second wavelength light pattern P translationally displaced relative to the first position onto the inner surface 28 of the mouth. Typically, the projected pattern P of light of the second wavelength is translationally displaced relative to the first position by a distance D11 between the respective optical axes 98 and 100 of the first pattern generating optical element 94 and the second pattern generating optical element 96. For some applications, the first pattern generating optical element 94 and the second pattern generating optical element 96 project different light patterns, so that the structured light projector 22 projects (a) a first pattern P1 from the first pattern generating optical element 94 in a first position onto the inner surface 28 of the mouth, and (b) a second pattern P2 (different from the first pattern P1) from the second pattern generating optical element 96 translationally displaced relative to the first position onto the inner surface 28 of the mouth.

[0138] For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 are mounted within the sealed housing 30 such that the first semiconductor laser core 84 and the second semiconductor laser core 86 emit laser light 85 and 87, respectively, in the same direction. For some applications, the first pattern generating optical element 94 and the second pattern generating optical element 96 are respectively the first region 102 and the second region 104 of the common lens 106. It should be noted that all options described above regarding the positioning of the pattern generating optical element 38 apply mutatis mutandis to the first pattern generating optical element 94 and the second pattern generating optical element 96.

[0139] For some applications, first beam shaping optical element 90 and second beam shaping optical element 92 are first region 108 and second region 110, respectively, of a common lens 112. Alternatively, first beam shaping optical element 90 and second beam shaping optical element 92 are separate lenses (configuration not shown).

[0140] For some applications, the computer processor 88 simultaneously actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 so that the structured light projector 22 simultaneously projects a pattern P of each of two different wavelengths, or a first pattern P1 and a second pattern P2. The translational shift between the projected light patterns (described above) and the wavelength differences between the light patterns result in a dense distribution of structured light elements for digital 3D reconstruction of the inner surface of the mouth 28 while reducing interference between the patterns.

[0141] Alternatively, for some applications, the computer processor 88 actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 alternately, so that the structured light projector 22 alternately projects a pattern P of each of two different wavelengths, or a first pattern P1 and a second pattern P2. Actuating the first semiconductor laser core 84 and the second semiconductor laser core 86 in an alternating time-share manner provides the advantage of a dense distribution of structured light elements for digital 3D reconstruction of the intraoral surface 28 while reducing the amount of light projected into the oral cavity at any given time. This in turn helps maintain contrast, which otherwise may be reduced due to the reflective and slightly translucent nature of the teeth.

[0142] Now specific reference Fig.12. For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 share a common beam shaping optical element 114. The beam shaping optical element 114 is arranged so that the laser light 85 and 87 from each of the first semiconductor laser core 84 and the second semiconductor laser core 86 respectively (i) enter the beam shaping optical element 114 along different respective axes 116 and 118 of the beam shaping optical element 114, and (ii) subsequently impinge on the pattern generating optical element 38 at different respective angles ψ (psi) and ω (omega) such that the projected pattern P of each wavelength is angularly shifted about the optical axis 72 of the pattern generating optical element 38. It should be noted that the distance D between the emission point 42 of the semiconductor laser core 34 and the input face 44 of the beam shaping element 36 described above applies mutatis mutandis to the beam shaping optical element 114.

[0143] For some applications, the computer processor 88 simultaneously actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 so that the structured light projector 22 simultaneously projects a pattern P of each of two different wavelengths. The angular shift between the projected light patterns and the wavelength difference between the light patterns result in a dense distribution of structured light elements for digital 3D reconstruction of the inner surface of the mouth 28 while reducing interference between the patterns.

[0144] Alternatively, for some applications, the computer processor 88 alternately actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 so that the structured light projector 22 alternately projects a pattern P at each of two different wavelengths. Actuating the first semiconductor laser core 84 and the second semiconductor laser core 86 in an alternating time-sharing manner provides the advantage of a dense distribution of structured light elements for digital 3D reconstruction of the intraoral surface 28 while reducing the amount of light projected into the oral cavity at any given time. This in turn helps maintain contrast, which otherwise may be reduced due to the reflective and slightly translucent nature of the teeth. Actuating the first semiconductor laser core 84 and the second semiconductor laser core 86 in an alternating time-sharing manner also provides the advantage of a dense distribution of structured light elements for digital 3D reconstruction of the intraoral surface 28 while reducing interference between patterns.

[0145] Now specific reference Figure 13-14B For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 have the same wavelength, that is, they project laser light of the same color. Figure 1 As shown), the first semiconductor laser core 84 and the second semiconductor laser core 86 having the same wavelength are typically actuated alternately. Fig.13A first semiconductor laser core 84 and a second semiconductor laser core 86 are shown with respective beam shaping optical elements 90 and 92 and respective pattern generating optical elements 94 and 96, such as described above with reference to FIG. Fig.11 as described above, mutatis mutandis.

[0146] Figure 14A-14B A first semiconductor laser core 84 and a second semiconductor laser core 86 are shown sharing a common beam shaping optical element 114, such as described above with reference to Fig.12 as described above, mutatis mutandis.

[0147] For some applications, the semiconductor laser cores 84 and 86 have the same wavelength, share a common beam shaping optical element 114, and the angles ψ and ω are equal to integer multiples of the diffraction angle of the pattern generating optical element 38, so that the two patterns P overlap. In this case, the computer processor 88 can simultaneously actuate the semiconductor laser cores 84 and 86 having the same wavelength. The overlapping patterns P of the same wavelength can result in approximately the same number of structured light features projected onto the inner surface 28 of the mouth as when only one semiconductor laser core is actuated, but with reduced speckle noise.

[0148] refer to Fig. 14B In one embodiment, a dual focus projector is implemented. For the dual focus projector, there is an axial offset 141 between the first semiconductor laser core 84 and the second semiconductor laser core 86. The axial offset results in two focal planes or focal planes. The first semiconductor laser core 84 (which has a larger distance from the shared common beam shaping optical element 114) has a first focal plane 143. The second semiconductor laser core 86 (which has a smaller distance from the shared common beam shaping optical element 114) has a second focal plane 145. In some embodiments, the focal plane is a focal plane. In some embodiments, the focal plane is a non-flat focal plane (e.g., a spherical focal plane). As shown, due to the axial offset 141, the first focal plane 143 has a larger distance from the pattern generating optical element 38 than the second focal plane 145. Therefore, the axial offset causes the first semiconductor laser core 84 to be associated with the first focal plane 143, and causes the second semiconductor laser core 86 to be associated with a different second focal plane 145. In one embodiment, the axial offset 141 is between about 1 μm and about 6 μm (e.g., 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, etc.). In one embodiment, the offset between the first focal plane 143 and the second focal plane 145 is about 1.7 mm to about 10 mm (e.g., 1.7 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, etc.).

[0149] In some embodiments, the first semiconductor laser core 84 and the second semiconductor laser core 86 operate in parallel (e.g., simultaneously). In some embodiments, the first semiconductor laser core 84 and the second semiconductor laser core 86 operate in series. In an example, the structured light projector 22 can alternate between actuation of the first semiconductor laser core 84 and the second semiconductor laser core 86 over time (e.g., performing a temporal alternation between the first semiconductor laser core 84 and the second semiconductor laser core 86). In an embodiment, such temporal alternation between the first semiconductor laser core 84 and the second semiconductor laser core 86 results in a dual-focus projection. This dual-focus projection can be similar to the dual-focus projection that can be achieved using a focusing mechanism that changes focus over time (e.g., by changing the position of a focusing lens), but without any moving parts.

[0150] In one embodiment, the computer processor 88 actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 alternately so that the structured light projector 22 alternately projects the pattern P, or the first pattern P1 and the second pattern P2 at different focal planes 143, 145. In one embodiment, the computer processor 88 actuates the first semiconductor laser core 84 and the second semiconductor laser core alternately according to a preprogrammed sequence. In one embodiment, the computer processor 88 dynamically actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 alternately based on one or more distances from the object being measured and / or based on other characteristics of the object being measured.

[0151] Now specific reference Fig.15 . For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 are mounted within the sealed housing 30, for example, on a common base 60 within the sealed housing 30, so that the first semiconductor laser core 84 and the second semiconductor laser core 86 emit lasers 85 and 87 in different directions, effectively creating two separate structured light projectors without having to occupy additional space within the probe 24. For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 are arranged so that they emit lasers 85 and lasers 87 in opposite directions. When the computer processor 88 actuates the first semiconductor laser core 84 and the second semiconductor laser core 86, the structured light projector 22 projects a first pattern P in a first direction and a second pattern P in a second direction.

[0152] The light source 32 comprises two separate beam shaping optical elements 36 arranged so that the laser light 85 from the first semiconductor laser core 84 and the laser light 87 from the second semiconductor laser core 86 enter and subsequently leave the respective beam shaping optical elements 36. It should be noted that the distance D between the emission point 42 of the semiconductor laser core and the input face 44 of the beam shaping optical element as described above applies mutatis mutandis to the case of Fig.15 The two beam shaping optical elements 36 are shown. The structured light projector 22 includes a first pattern generating optical element and a second pattern generating optical element 38, which are arranged so that the laser light 85 and the laser light 87 enter the first pattern generating optical element and the second pattern generating optical element 38, respectively. For some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 have the same wavelength. Alternatively, for some applications, the first semiconductor laser core 84 and the second semiconductor laser core 86 have different wavelengths.

[0153] For some applications, the computer processor 88 actuates the first semiconductor laser core 84 and the second semiconductor laser core 86 so that the structured light projector 22 alternately projects the first pattern P along the first direction and the second pattern P along the second direction. Alternatively, for some applications, the computer processor 88 actuates the first semiconductor laser core and the second semiconductor laser core so that the structured light projector 22 simultaneously projects the first pattern P along the first direction and the second pattern P along the second direction.

[0154] Now specific reference Fig.16 . Fig.16 A specific example is shown in which a first semiconductor laser core 84 and a semiconductor laser core 86 are mounted to a common base 60 within a sealed housing 30, and the respective first pattern generating optical elements and second pattern generating optical elements 38 are arranged such that there is a respective angle β between (a) the respective optical axis 62 of each beam shaping optical element 36 and (b) the respective optical axis 72 of each pattern generating optical element 38, the angle being at least 50 degrees and / or less than 100 degrees. A respective folding mirror 82 is disposed within the probe 24 and is positioned to reflect laser light 85 and 87 leaving the respective beam shaping optical element 36 toward the respective pattern generating optical element 38. It should be noted that the above reference to Fig.10 All matters described with respect to the total distance travelled by the laser light from leaving the beam shaping optics to entering the pattern generating optics apply mutatis mutandis to Fig.16 It should be noted that the distance D between the emission point 42 of the semiconductor laser core 34 and the input face 44 of the beam shaping element 36 described above applies mutatis mutandis to the example Fig.16 A first beam shaping optical element and a second beam shaping optical element 36 are shown.

[0155] Reference now Fig.17 , which is a schematic diagram of a structured light projector 22 according to some applications of the present invention, having a single semiconductor laser core 34, a single beam shaping optical element 36, and corresponding first and second pattern generating optical elements 94, 96. For some applications, the first and second pattern generating optical elements 94, 96 are two corresponding areas 120 and 122 on a common substrate 124, which includes a beam splitter 126 and a reflector 128 disposed within the substrate 124. When the computer processor 88 actuates the semiconductor laser core 34, the laser light 39 leaving the light source 32 is split into a first beam 130 and a second beam 132 by the beam splitter 126 within the substrate 124. The first beam 130 enters the first pattern generating optical element 94, and the second beam 132 is reflected by the reflector 128 toward the second pattern generating optical element 96 to produce two separate projection patterns P, which are shifted relative to each other by a distance D12 between the optical axes 98 and 100 of the first and second pattern generating optical elements 94, 96. The two separate projection patterns together enable the structured light projector 22 to have a wider field of view.

[0156] Applications of the invention described herein may take the form of a computer program product accessible from a computer-usable or computer-readable medium (e.g., a non-transitory computer-readable medium) that provides program code for use by or in conjunction with a computer or any instruction execution system (such as a computer processor 88). For the purposes of this description, a computer-usable or computer-readable medium may be any device that may contain, store, communicate, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or apparatus. The medium may be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or device or apparatus) or a propagation medium. Typically, a computer-usable or computer-readable medium is a non-transitory computer-usable or computer-readable medium.

[0157] Examples of computer readable media include semiconductor or solid-state memory, magnetic tape, removable computer disk, random access memory (RAM), read-only memory (ROM), hard disk, and optical disk. Current examples of optical disks include compact disk - read only memory (CD-ROM), compact disk - read / write (CD-R / W), and DVD. For some applications, cloud storage and / or storage in a remote server is used.

[0158] A data processing system suitable for storing and / or executing program code will include at least one processor (e.g., computer processor 88) directly or indirectly coupled to a memory element via a system bus. The memory element may include local memory, bulk storage, and cache memory used during the actual execution of the program code, which provides temporary storage of at least some program code to reduce the number of times the code must be retrieved from the bulk storage during execution. The system may read the creative instructions on the program storage device and follow these instructions to perform the method of an embodiment of the present invention.

[0159] A network adapter may be coupled to a processor to enable the processor to connect to other processors or to remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.

[0160] Computer program code for carrying out operations of the present invention may be written in any combination of one or more programming languages ​​including object oriented programming languages ​​such as Java, Smalltalk, C++ and traditional procedural programming languages ​​such as the C programming language or similar programming languages.

[0161] It should be understood that the methods described herein can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine, so that instructions executed via a processor of a computer (e.g., a computer processor 88) or other programmable data processing device create a device for implementing the functions / actions specified in the methods described in this application. These computer program instructions can also be stored in a computer-readable medium (e.g., a non-transitory computer-readable medium), which can instruct a computer or other programmable data processing device to act in a particular manner, so that the instructions stored in the computer-readable medium produce an article of instruction means including the functions / actions specified in the methods described in this application. The computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are performed on a computer or other programmable device to produce a computer-implemented process, so that the instructions executed on a computer or other programmable device provide a process for implementing the functions / actions specified in the methods described in this application.

[0162] The computer processor 88 is typically a hardware device programmed with computer program instructions to produce a special-purpose computer. For example, when programmed to perform the methods described herein, the computer processor typically acts as a special-purpose computer processor. Typically, the operations described herein performed by the computer processor convert the physical state of the memory (which is a real physical item) to have different magnetic polarity, charge, etc., depending on the technology of the memory used.

[0163] Those skilled in the art will appreciate that the present invention is not limited to what has been particularly shown and described above. On the contrary, the scope of the present invention includes the combination and sub-combination of the various features described above, as well as variations and modifications thereof that are not in the prior art that those skilled in the art will think of when reading the foregoing description.

Claims

1. A device for intraoral scanning, the device comprising: an elongated rod including a probe at a distal end of the elongated rod; as well as One or more structured light projectors are disposed in the probe, each structured light projector comprising: (a) Housing; (b) a light source, disposed in the housing and comprising: Semiconductor laser cores; and beam shaping optics; and (c) pattern generating optical element, in: The distance D between the emission point of the semiconductor laser core and the input face of the beam shaping optical element is 50-250 micrometers, and Each structured light projector is configured to project a light pattern onto an interior surface of a mouth when the light source of the structured light projector is actuated to emit light through the pattern generating optical element of the structured light projector.

2. The device according to claim 1, wherein The arrangement of the semiconductor laser core and the beam shaping optics within the housing together with the distance D of 50-250 micrometers allows the longest dimension of the housing to be 1.5-2.5 mm.

3. The device according to claim 1, wherein: The height of the shell is 1.6-2.4 mm.

4. The device according to claim 1, wherein: The beam shaping optical element is positioned within the housing such that at least 75% of the light emitted by the semiconductor laser core enters the beam shaping optical element.

5. The device according to claim 4, wherein: The beam shaping optical element is positioned within the housing such that 80-90% of the light emitted by the semiconductor laser core enters the beam shaping optical element.

6. The device according to claim 1, wherein: The housing includes metal, and the semiconductor laser core is disposed within the housing such that heat is conducted from the semiconductor laser core to the metal of the housing.

7. The device according to claim 6, wherein: The semiconductor laser core is mounted on a base within the housing so that heat is conducted from the semiconductor laser core through the base to the metal of the housing.

8. The device according to claim 7, wherein: The base is ceramic.

9. The apparatus of claim 1, further comprising one or more cameras disposed within the probe, wherein: The distance between (i) the optical axis of at least one camera and (ii) the optical axis of at least one structured light projector adjacent to the at least one camera is 3-5 mm.

10. The device according to claim 9, wherein: (a) the probe includes a transparent window, the one or more structured light projectors project light through the transparent window, and the one or more cameras receive light through the transparent window, and (b) the distance from the transparent window where 50% overlap of the corresponding fields of view of at least one camera and at least one adjacent structured light projector is 2-6 mm.

11. The device according to claim 9, wherein: (a) the probe includes a transparent window, the one or more structured light projectors project light through the transparent window, and the one or more cameras receive light through the transparent window, and (b) the distance from the transparent window where the corresponding fields of view of at least one camera and at least one adjacent structured light projector begin to overlap is 1-3 mm.

12. The device according to claim 1, wherein: The housing includes a transparent window through which light exits the housing, and the transparent window includes the pattern generating optical element.

13. The apparatus of claim 12, wherein: The angle between the optical axis of the beam shaping optical element and the optical axis of the pattern generating optical element is 65-120 degrees, and The apparatus also includes a reflector disposed within the housing and positioned to reflect light exiting the beam shaping optical element toward the pattern generating optical element.

14. The apparatus according to claim 1, wherein: The pattern generating optical element is disposed within the probe and outside the housing, and the distance traveled by light from leaving the beam shaping optical element to entering the pattern generating optical element is 2-8 mm.

15. The apparatus according to claim 1, wherein: The pattern generating optical element is disposed within the probe and outside the housing, and the distance traveled by light from leaving the beam shaping optical element to entering the pattern generating optical element is 8-25 mm.

16. The apparatus of claim 1, wherein: The pattern generating optical element is arranged inside the probe and outside the housing so that the angle between the optical axis of the beam shaping optical element and the optical axis of the pattern generating optical element is 50-100 degrees, The apparatus further includes a reflector disposed within the probe and positioned to reflect light exiting the beam shaping optical element toward the pattern generating optical element, and The distance travelled by light from leaving the beam shaping optical element to entering the pattern generating optical element is 8-25 mm.

17. The apparatus according to claim 1, wherein: For at least one of the one or more structured light projectors, the semiconductor laser core is a first semiconductor laser core and the light source further includes a second semiconductor laser core.

18. The apparatus according to claim 17, wherein: The first semiconductor laser core and the second semiconductor laser core are mounted on a common base within the housing.

19. The apparatus according to claim 17, wherein: The first semiconductor laser core and the second semiconductor laser core have different wavelengths, and the device also includes a computer processor, which is configured to actuate the first semiconductor laser core and the second semiconductor laser core so that the at least one structured light projector projects a pattern of each of the different wavelengths.

20. The apparatus of claim 19, wherein: The computer processor is configured to alternately actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector alternately projects a pattern at each of the different wavelengths.

21. The apparatus of claim 19, wherein: The computer processor is configured to simultaneously actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector simultaneously projects a pattern at each of the different wavelengths.

22. The apparatus of claim 19, wherein: The beam shaping optical element is a first beam shaping optical element, and the light source further comprises a second beam shaping optical element, the first beam shaping optical element and the second beam shaping optical element being arranged such that laser light from the first semiconductor laser core enters and then leaves the first beam shaping optical element, and laser light from the second semiconductor laser core enters and then leaves the second beam shaping optical element, and The pattern generating optical element is a first pattern generating optical element, and the at least one structured light projector also includes a second pattern generating optical element, and the first pattern generating optical element and the second pattern generating optical element are arranged so that the laser light leaving the first beam forming optical element enters the first pattern generating optical element, and the laser light leaving the second beam forming optical element enters the second pattern generating optical element.

23. The apparatus of claim 22, wherein: The first pattern generating optical element and the second pattern generating optical element project the same light pattern, so that the at least one structured light projector projects (a) a light pattern of a first wavelength in a first position onto the inner surface of the mouth, and projects (b) a light pattern of a second wavelength translationally shifted relative to the first position onto the inner surface of the mouth.

24. The apparatus of claim 23, wherein: The distance by which the projection pattern of light of the second wavelength is translationally displaced relative to the first position is the distance between the optical axis of the first pattern generating optical element and the optical axis of the second pattern generating optical element.

25. The apparatus of claim 22, wherein: The at least one structured light projector projects a first pattern from the first pattern generating optical element and a second pattern from the second pattern generating optical element, the first pattern being different from the second pattern.

26. The apparatus of claim 22, wherein: The first and second semiconductor laser cores are mounted in the housing so that they emit laser light in the same direction, and the first and second pattern generating optical elements are first and second regions of a common lens, respectively.

27. The apparatus of claim 22, wherein: The first semiconductor laser core and the second semiconductor laser core are mounted in the housing so that they emit laser light in the same direction, and the first beam shaping optical element and the second beam shaping optical element are respectively a first region and a second region of a common lens.

28. The apparatus of claim 22, wherein: The first beam shaping optical element comprises a first lens and the second beam shaping optical element comprises a second lens, the first lens being separate from the second lens.

29. The apparatus of claim 19, wherein: The beam shaping optical element is arranged so that laser light from each of the first semiconductor laser core and the second semiconductor laser core (i) enters the beam shaping optical element along a different respective axis of the beam shaping optical element and (ii) subsequently impinges on the pattern generating optical element at a different respective angle such that the projected pattern of each wavelength is angularly shifted around the optical axis of the pattern generating optical element.

30. The apparatus of claim 17, wherein: The first and second semiconductor laser cores have the same wavelength, and the apparatus further includes a computer processor configured to alternately actuate the first and second semiconductor laser cores.

31. The apparatus of claim 30, wherein: The beam shaping optical element is a first beam shaping optical element, and the light source further comprises a second beam shaping optical element, the first beam shaping optical element and the second beam shaping optical element being arranged such that laser light from the first semiconductor laser core enters and then leaves the first beam shaping optical element, and laser light from the second semiconductor laser core enters and then leaves the second beam shaping optical element, and The pattern generating optical element is a first pattern generating optical element, and the at least one structured light projector also includes a second pattern generating optical element, and the first pattern generating optical element and the second pattern generating optical element are arranged so that the laser light leaving the first beam forming optical element enters the first pattern generating optical element, and the laser light leaving the second beam forming optical element enters the second pattern generating optical element.

32. The apparatus of claim 31, wherein: The first pattern generating optical element and the second pattern generating optical element project the same light pattern, so that the at least one structured light projector alternately projects (a) the light pattern in a first position onto the inner surface of the mouth, and (b) the light pattern translationally shifted relative to the first position onto the inner surface of the mouth.

33. The apparatus of claim 31, wherein: The at least one structured light projector alternately projects a first pattern from the first pattern generating optical element and a second pattern from the second pattern generating optical element, the first pattern being different from the second pattern.

34. The apparatus of claim 31, wherein: The first and second semiconductor laser cores are mounted in the housing so that they emit laser light in the same direction, and the first and second pattern generating optical elements are first and second regions of a common lens, respectively.

35. The apparatus of claim 31, wherein: The first semiconductor laser core and the second semiconductor laser core are mounted in the housing so that they emit laser light in the same direction, and the first beam shaping optical element and the second beam shaping optical element are respectively a first region and a second region of a common lens.

36. The apparatus of claim 31, wherein: The first beam shaping optical element comprises a first lens and the second beam shaping optical element comprises a second lens, the first lens being separate from the second lens.

37. The apparatus of claim 30, wherein: The beam shaping optical element is arranged so that laser light from each of the first semiconductor laser core and the second semiconductor laser core (i) enters the beam shaping element along a different respective axis of the beam shaping optical element and (ii) subsequently impinges on the pattern generating optical element at different respective angles, so that the at least one structured light projector projects a pattern that is alternately angularly shifted around the optical axis of the pattern generating optical element.

38. The apparatus of claim 37, wherein: The first semiconductor laser core is axially offset relative to the second semiconductor laser core.

39. The apparatus of claim 38, wherein: The axial offset causes the first semiconductor laser core to be associated with a first focal plane and the second semiconductor laser core to be associated with a second focal plane.

40. The apparatus of claim 39, wherein: The offset between the first focal plane and the second focal plane is about 1.7 mm to about 10 mm.

41. The apparatus of claim 39, wherein: The apparatus is configured to alternate between actuating the first semiconductor laser core to obtain the first focal plane and actuating the second semiconductor laser core to obtain the second focal plane.

42. The apparatus of claim 38, wherein: The axial offset is about 1 μm to about 6 μm.

43. The apparatus of claim 1, wherein: For at least one of the one or more structured light projectors: The semiconductor laser core is a first semiconductor laser core, and the light source further includes a second semiconductor laser core, the first semiconductor laser core and the second semiconductor laser core are mounted in the housing so that the first semiconductor laser core and the second semiconductor laser core emit laser light in respective first and second directions, the first direction being different from the second direction, and The apparatus also includes a computer processor configured to actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector projects a first pattern along the first direction and a second pattern along the second direction.

44. The apparatus of claim 43, wherein: The first semiconductor laser core and the second semiconductor laser core are mounted on a common base within the housing.

45. The apparatus of claim 43, wherein: The beam shaping optical element is a first beam shaping optical element, and the light source further comprises a second beam shaping optical element, the first beam shaping optical element and the second beam shaping optical element being arranged such that laser light from the first semiconductor laser core enters and then leaves the first beam shaping optical element, and laser light from the second semiconductor laser core enters and then leaves the second beam shaping optical element, and The pattern generating optical element is a first pattern generating optical element, and the at least one structured light projector also includes a second pattern generating optical element, and the first pattern generating optical element and the second pattern generating optical element are arranged so that the laser light leaving the first beam forming optical element enters the first pattern generating optical element, and the laser light leaving the second beam forming optical element enters the second pattern generating optical element.

46. ​​The apparatus of claim 43, wherein: The first semiconductor laser core and the second semiconductor laser core have the same wavelength.

47. The apparatus of claim 43, wherein: The first semiconductor laser core and the second semiconductor laser core have different wavelengths.

48. The apparatus of claim 43, wherein: The first direction and the second direction are opposite to each other.

49. The apparatus of claim 43, wherein: The computer processor is configured to actuate the first semiconductor laser core and the second semiconductor laser core so that the at least one structured light projector alternately projects the first pattern along the first direction and projects the second pattern along the second direction.

50. The apparatus of claim 43, wherein: The computer processor is configured to actuate the first semiconductor laser core and the second semiconductor laser core such that the at least one structured light projector simultaneously projects the first pattern along the first direction and the second pattern along the second direction.

51. The apparatus of claim 1, wherein: For at least one of the one or more structured light projectors: The pattern generating optical element is a first pattern generating optical element and the at least one structured light projector further comprises a second pattern generating optical element, The first pattern generating optical element and the second pattern generating optical element are two corresponding areas on a common substrate, the common substrate comprising a beam splitter and a reflector disposed within the common substrate, and The apparatus further comprises a computer processor configured to actuate the semiconductor laser core such that: The laser light leaving the light source is split into a first light beam and a second light beam by the beam splitter in the common substrate, and The first light beam enters the first pattern generating optical element and the second light beam is reflected by the reflector toward the second pattern generating optical element to produce two separate projected patterns that are translationally displaced relative to each other.

52. The apparatus of claim 51, wherein: The first light beam enters the first pattern generating optical element, and the second light beam is reflected by the reflector toward the second pattern generating optical element to generate two separate projection patterns, and the distance by which the two separate projection patterns are shifted relative to each other is the distance between the optical axis of the first pattern generating optical element and the optical axis of the second pattern generating optical element.

53. The apparatus according to any one of claims 1 to 52, wherein: The housing is a sealed housing.

54. A device for intraoral scanning, the device comprising: an elongated rod including a probe at a distal end of the elongated rod; as well as One or more structured light projectors are disposed in the probe, each structured light projector comprising: (a) Housing; (b) a light source, disposed in the housing and comprising: Semiconductor laser cores; and beam shaping optics; and (c) pattern generating optical element, in: The semiconductor laser core and the beam shaping optical element are disposed in a common cavity of the housing, and Each structured light projector is configured to project a light pattern onto an interior surface of a mouth when the light source of the structured light projector is actuated to emit light through the pattern generating optical element of the structured light projector.

55. The apparatus of claim 54, wherein: The housing is a sealed housing.

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