Optical module and three-dimensional scanner having the same mounted thereon, as well as method for adjusting three-dimensional scanner

Abstract

To prevent a reduction in measurement accuracy in a three-dimensional scanner.SOLUTION: An optical module is used for a three-dimensional scanner that acquires three-dimensional shape information of an object with light from a light source by using a focusing method, and comprises a sensor, a beam splitter, a pattern plate, a housing, and a shim. The sensor detects the light from the light source reflected on the object, and the beam splitter splits the light into an optical path reaching the object from the light source and an optical path reaching the sensor from the object. The pattern plate is arranged between the light source and the beam splitter and configured to project a reference pattern on the sensor with the light from the light source. The sensor, the beam splitter, and the pattern plate are arranged in the housing. The shim adjusts the distance between the pattern plate and the beam splitter. The housing has a recess for arranging the pattern plate. The pattern plate is rotatably supported in the recess within a predetermined angle range around an optical axis of the light from the light source.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an optical module in a three-dimensional scanner for acquiring three-dimensional shape information of an object. [Background technology]

[0002] In recent years, in the field of dentistry, it has become necessary to acquire three-dimensional shape information of teeth in order to digitally design prostheses and the like on a computer, and three-dimensional scanners (intraoral scanners) have been put to practical use. JP 2023-86340 A (Patent Document 1) discloses a three-dimensional scanner that acquires three-dimensional shape information of an object using a focusing method. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-86340 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-described three-dimensional scanner has an optical module incorporating a beam splitter that splits light from a light source and an image sensor that detects light from the light source reflected by an object. If the optical components incorporated in the optical module are displaced from their desired design positions, causing deviations in the relative positions and angles between the components, the measurement accuracy of the three-dimensional scanner can be reduced. The present disclosure has been made to solve this problem, and its purpose is to prevent a reduction in measurement accuracy in a three-dimensional scanner. [Means for solving the problem]

[0005] The optical module according to the present disclosure is used in a three-dimensional scanner that acquires three-dimensional shape information of an object using a focusing method with light from a light source. The optical module includes a sensor, a beam splitter, a pattern plate, a housing, and a shim. The sensor detects light from the light source reflected by the object. The beam splitter separates an optical path from the light source to the object from an optical path from the object to the sensor. The pattern plate is disposed between the light source and the beam splitter and configured to project a reference pattern onto the sensor using light from the light source. The sensor, beam splitter, and pattern plate are disposed in the housing. The shim is disposed between the pattern plate and the beam splitter within the housing and adjusts the distance between the pattern plate and the beam splitter. The housing has a recess for disposing the pattern plate. The pattern plate is supported within the recess so as to be rotatable within a predetermined angular range around the optical axis of the light from the light source.

[0006] The adjustment method according to the present disclosure is an adjustment method for a three-dimensional scanner that acquires three-dimensional shape information of an object using a focusing method. The three-dimensional scanner includes a light source that irradiates light onto the object and an optical module arranged on an optical axis from the light source to the object. The optical module includes a sensor, a beam splitter, a pattern plate, a housing, and a shim. The sensor detects light from the light source reflected by the object. The beam splitter separates an optical path from the light source to the object from an optical path from the object to the sensor. The pattern plate is arranged between the light source and the beam splitter and is configured to project a reference pattern onto the sensor using light from the light source. The sensor, beam splitter, and pattern plate are arranged in the housing. The shim is arranged between the pattern plate and the beam splitter within the housing. The shim is used to adjust the distance between the pattern plate and the beam splitter. The sensor is an imaging sensor. The shim includes one or more flat plate members. The adjustment method includes the steps of (i) determining whether the distance between the pattern plate and the beam splitter is within a predetermined range based on the image of the reference pattern projected onto the sensor and the imaging area of ​​the sensor; (ii) determining the number of flat plate members to be used for the shim based on the results of the determining step; (iii) detecting the positional deviation of the pattern plate in the housing in the rotational direction around the optical axis based on the image of the reference pattern projected onto the sensor and the imaging area of ​​the sensor; and (iv) adjusting the position of the pattern plate based on the detection results. [Effects of the Invention]

[0007] In the optical module for a three-dimensional scanner according to the present disclosure, the distance between the pattern plate and the beam splitter can be adjusted using a shim. Furthermore, since the pattern plate is supported rotatably within a predetermined angular range around the optical axis of the light from the light source, the rotational deviation of the pattern plate relative to the optical axis can be adjusted. This reduces deviations from the designed positions of the relative positions and relative angles between the components within the optical module when assembling the optical module. Therefore, a decrease in the measurement accuracy of the three-dimensional scanner can be prevented. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating the overall configuration of a three-dimensional scanner according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view for explaining an optical configuration within the handpiece in FIG. [Figure 3] FIG. 2 is an exploded perspective view for explaining the details of the optical module in FIG. [Figure 4] FIG. 10 is a perspective view of a state in which the pattern plate is incorporated into the holder. [Figure 5] FIG. [Figure 6] FIG. 2 is a perspective view showing a state in which the holder is incorporated into the housing. [Figure 7] 7 is a plan view of the housing of FIG. 6 as viewed from the X-axis direction. [Figure 8] 10A and 10B are diagrams illustrating a state in which a rotational deviation occurs in the pattern plate relative to the imaging area of ​​the image sensor. [Figure 9] FIG. 10 is a diagram showing a state in which no rotational misalignment occurs in the pattern plate. [Figure 10] 10 is a flowchart illustrating a method for adjusting the optical module. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0010] [Overall configuration of the 3D scanner] FIG. 1 shows the overall configuration of a three-dimensional scanner 10 according to an embodiment. The three-dimensional scanner 10 is an intraoral scanner (IOS) that scans the surface shape of an object, such as teeth and soft tissues in the oral cavity, to obtain three-dimensional data of the surface shape. The three-dimensional data includes position information (coordinates of the vertical, horizontal, and height axes) of each of a point cloud (multiple points) that indicates the surface shape of the object. The three-dimensional scanner 10 can also obtain color data that indicates the color of each of the point cloud (multiple points) that indicates the surface shape of the object, along with the three-dimensional data.

[0011] The three-dimensional scanner 10 according to the embodiment can be applied not only to dentistry but also to all medical fields such as ophthalmology, otolaryngology, radiology, internal medicine, surgery, and veterinary medicine. For example, the three-dimensional scanner 10 according to the embodiment is not limited to intraoral scanners, but can also be applied to other three-dimensional scanners having a similar configuration, such as a scanner that acquires three-dimensional data of the surface shape of the outer ear by imaging the inside of a human ear in addition to the inside of the oral cavity.

[0012] The user of the three-dimensional scanner 10 may be any person who acquires three-dimensional data of objects such as teeth and soft tissues using the three-dimensional scanner 10, such as a dentist or other practitioner, a dental assistant, a professor or student at a dental school, a dental technician, a manufacturer's engineer, or a worker at a manufacturing plant. The subject of scanning with the three-dimensional scanner 10 may be anyone who can be scanned by the three-dimensional scanner 10, such as a patient at a dental clinic or a subject at a dental school.

[0013] 1, the three-dimensional scanner 10 comprises a handpiece 100, a control device 20, a power supply 30, and a display 40. The handpiece 100 is a handheld member, and comprises an elongated main body 120 and a probe 110 provided at the tip of the main body 120. A scanner tip (not shown) is detachably attached to the probe 110.

[0014] The probe 110 is attached to the main body 120 and has a shape that can fit into the base of the scanner tip. The probe 110 is inserted into the oral cavity with the scanner tip attached, and projects light having a pattern (hereinafter simply referred to as "pattern") onto an object such as teeth and soft tissue. The probe 110 receives the light reflected from the object onto which the pattern is projected and guides it to the main body 120. The scanner tip covers the outer periphery of the probe 110 and is detachably attached to the probe 110.

[0015] The handpiece 100 projects a pattern onto an object via a probe 110 equipped with a scanner tip and captures an image of the projected pattern. Although the handpiece 100 is configured to acquire a three-dimensional shape using the focusing principle, it may be configured to acquire a three-dimensional shape using other principles, such as the confocal method or trigonometry. In other words, the handpiece 100 may be configured to use any principle as long as it is configured to acquire a three-dimensional shape using an optical method.

[0016] The control device 20 controls the operation of the handpiece 100 and processes images captured by the handpiece 100 to obtain a three-dimensional shape. The control device 20 can output three-dimensional data corresponding to the obtained three-dimensional shape to the display 40. The control device 20 can also input information such as settings for the handpiece 100 via an input device (not shown).

[0017] In the three-dimensional scanner 10 according to the embodiment, the control device 20 is configured as a separate entity from the handpiece 100, but if the control device 20 is small and light enough to be lifted with one hand, some or all of the functions of the control device 20 may be incorporated into the handpiece 100.

[0018] The display 40 displays the three-dimensional shape of the object represented by the three-dimensional data obtained by the control device 20. The display 40 can also display other information, such as setting information for the handpiece 100, patient information, the startup status of the three-dimensional scanner 10, an instruction manual, and a help screen. The display 40 may be, for example, a stationary liquid crystal display, a head-mounted display, or a wearable display in the form of glasses. The three-dimensional scanner 10 may be equipped with multiple displays 40, and the three-dimensional shape of the object and other information may be displayed simultaneously or in separate displays 40.

[0019] The power supply 30 supplies power to the handpiece 100 and the control device 20. The power supply 30 may be provided outside the control device 20, or may be provided inside the control device 20 or inside the handpiece 100. Note that the three-dimensional scanner 10 may include multiple power supplies 30 capable of supplying power to each of the handpiece 100, the control device 20, and the display 40.

[0020] In the example of Figure 1, the handpiece 100, control device 20, power supply 30, and display 40 of the three-dimensional scanner 10 are depicted as being connected by cables, but some or all of these cables may be connected by wireless communication.

[0021] [Handpiece configuration] 2 is a cross-sectional view illustrating the optical configuration of handpiece 100 in FIG. 1. In handpiece 100, lens 161 and mirror 170 are disposed within probe 110, and light source 140, optical module 150, and focusing lens 162 are disposed within main body 120. Lens 161 and focusing lens 162 form objective optical system 160. In the following description, the axis along the width direction of main body 120 of handpiece 100 is defined as the X-axis, the axis along the depth direction of main body 120 is defined as the Y-axis, and the axis along the height direction of main body 120 is defined as the Z-axis.

[0022] The light source 140 includes a light-emitting element 141 and a light source lens 142. The light-emitting element 141 is, for example, an LED (Light Emitting Diode), and the amount of light emitted can be adjusted by changing the amount of current supplied to the LED by a driver circuit (not shown). The light-emitting element 141 may be a point light source provided with a single LED or laser element, or may be an array light source in which multiple element light sources such as LEDs or laser elements are arranged on a substrate. A multi-color light source such as a three-primary color LED may also be used. The light source lens 142 uniformizes the light emitted from the light-emitting element 141 and irradiates the optical module 150 with the light.

[0023] The optical module 150 includes a beam splitter 151, an image sensor 152, and a pattern plate 153. The beam splitter 151 is, for example, a prism, and is an optical component that separates an optical path from the light source 140 to the object and an optical path from the object to the image sensor 152.

[0024] The image sensor 152 is, for example, a charge coupled device (CCD) image sensor or a complementary metal-oxide-semiconductor (CMOS) image sensor, and is disposed on the substrate 130. The image sensor 152 captures an image of the light reflected by the beam splitter 151 from the object.

[0025] The pattern plate 153 is disposed between the light source 140 and the beam splitter 151. The pattern plate 153 is a filter that imparts an intensity pattern, such as a line pattern or a checkered pattern, to the light emitted from the light source 140, and projects the pattern onto the surface of the target object.

[0026] The focusing lens 162 is fixed on a slider (not shown) that is movable in the optical axis direction (X-axis direction), and the movement of the slider in the X-axis direction changes the focal position of the object and the focal position of the image sensor 152. By changing the position of the focusing lens 162, the focal position FP of the object can be changed between a position close to the output end face of the handpiece 100 and a position far from the output end face.

[0027] Light emitted from light source 140 and passing through focusing lens 162 is irradiated onto an object via lens 161 and mirror 170. Lens 161 is an optical component that focuses light that has passed through focusing lens 162 onto the object. Mirror 170 is an optical component that changes the direction of light from light source 140 and light reflected by the object. The configurations of lens 161 and mirror 170 are merely examples, and the configurations may be changed as necessary.

[0028] When acquiring a three-dimensional shape using the focusing method, light passing through pattern plate 153 is projected onto the object. As focusing lens 162 moves back and forth linearly on the optical axis, the focal position of the projection pattern on the object changes. Under the control of control device 20 (FIG. 1), image sensor 152 detects light from the object at a predetermined frame rate each time the focal position of the projection pattern changes, thereby capturing an image of the object located at the focal position of the projection pattern. Control device 20 calculates shape information of the object based on the position of focusing lens 162 and the detection result by image sensor 152 at that time, thereby acquiring three-dimensional data of the surface shape of the object.

[0029] [Optical module configuration] Next, the detailed configuration of the optical module 150 will be described with reference to Figures 3 to 7. Figure 3 is an exploded perspective view of the optical module 150.

[0030] Referring to FIG. 3, the optical module 150 includes a beam splitter 151, an image sensor 152, and a pattern plate 153, as well as a holder 154, a housing 155, and a shim 156.

[0031] The holder 154 is a container for holding the pattern plate 153. Fig. 4 is a perspective view of the holder 154 with the pattern plate 153 assembled therein. Fig. 5 is a plan view of the holder 154.

[0032] 5, holder 154 is an annular member with a circular opening formed inside. The outer shape of holder 154 is generally a combination of a square and a circle whose centers coincide with each other, with circular portions 1541 protruding from each side of the square.

[0033] The holder 154 has a recess in the thickness direction that is adapted to the shape of the pattern plate 153, and the pattern plate 153 having a square flat plate shape is fixed in the recess.

[0034] A substantially elliptical through-hole 1542 is formed in opposing circular portions 1541 of holder 154. As shown in Fig. 3, holder 154 is fixed to housing 155 by inserting fastening members 158 such as screws into through-holes 1542.

[0035] The housing 155 has a generally cylindrical shape with its axis oriented in the X-axis direction, and houses the beam splitter 151 and the pattern plate 153 held by the holder 154 inside.

[0036] Fig. 6 is a perspective view of the state in which holder 154 is incorporated into housing 155. Fig. 7 is a plan view of housing 155 in Fig. 6 as viewed from the X-axis direction. Note that in Figs. 6 and 7, the positive direction of the Z-axis is downward in the drawings.

[0037] A recess 1551 is formed on the end face of housing 155 facing in the negative direction of the X axis, for arranging holder 154 on which pattern plate 153 is arranged. The shape of the inner wall of recess 1551 corresponds to the outer shape of holder 154, and is a shape that generally combines a positive direction and a circle. When holder 154 is arranged in recess 1551, a small gap is formed between guide portion 1552 formed in an arc shape on the inner wall of housing 155 and circular portion 1541 of holder 154.

[0038] Holder 154 is configured to be rotatable within a predetermined angular range around the X axis along guide portion 1552 when not fixed with fastening member 158. Fig. 7 shows an example in which holder 154 is rotated counterclockwise (CCW) in recess 1551 of housing 155. As described above, through-hole 1542 formed in holder 154 has a substantially elliptical shape, and therefore holder 154 can be fixed to housing 155 in a state in which holder 154 is rotated to a desired position.

[0039] An opening 1554 is formed in the surface of the housing 155 facing the negative direction of the Z axis. The beam splitter 151 is disposed inside the housing 155 through the opening 1554. The light reflected from the object by the beam splitter 151 is guided to the image sensor 152 through the opening 1554.

[0040] 3 again, shim 156 is a flat plate-shaped member that is placed between holder 154 and the bottom of recess 1551 of housing 155 when holder 154 is attached to housing 155. Shim 156 is used to adjust the distance between beam splitter 151 and pattern plate 153.

[0041] 3 shows an example in which three flat plate members 1561, 1562, and 1563 are used as the shim 156, but the number of flat plate members is not limited to this. The thickness of the flat plate members is, for example, 0.05 mm, 0.10 mm, or 0.15 mm. By adjusting the thickness and number of the flat plate members, the distance between the beam splitter 151 and the pattern plate 153 can be adjusted to a desired design distance. The base material of each flat plate member is, for example, stainless steel or aluminum.

[0042] In a three-dimensional scanner, a pattern generated by pattern plate 153 is projected onto an object, and the light reflected from the object is captured by image sensor 152, thereby obtaining data on the three-dimensional shape of the object. Therefore, if there is a deviation in the relative position and relative angle of the pattern generated by pattern plate 153 with respect to the imaging area of ​​image sensor 152, it may not be possible to obtain correct three-dimensional shape data, resulting in reduced measurement accuracy.

[0043] On the other hand, as described above, optical module 150 is configured by combining multiple parts, and there may be some variation in assembly accuracy due to processing errors during the manufacture of each part, etc. Therefore, when assembling optical module 150, an adjustment mechanism is required to adjust the positional relationship between image sensor 152 and pattern plate 153.

[0044] In optical module 150 of this embodiment, the amount of deviation in distance along the optical path can be adjusted by disposing shim 156 between holder 154 that holds pattern plate 153 and housing 155. Furthermore, by configuring holder 154 to be rotatable around the optical axis with respect to housing 155, the relative angle of image sensor 152 with respect to the imaging area can be adjusted.

[0045] 8 and 9 are diagrams showing an example of a pattern projected onto the imaging area of ​​the image sensor 152. Fig. 8 is a diagram showing a case where a rotational deviation of the pattern plate 153 occurs with respect to the imaging area of ​​the image sensor 152. On the other hand, Fig. 9 is a diagram showing a state where no rotational deviation of the pattern plate 153 occurs.

[0046] 8, the projected reference pattern 210 is shifted in the clockwise direction (CW direction) with respect to the imaging area 200 of the image sensor 152. In this case, by adjusting the holder 154 that holds the pattern plate 153 in the CCW direction, it is possible to correct the rotational shift of the pattern plate 153 with respect to the predetermined imaging area 200 as shown in FIG.

[0047] Furthermore, although not shown in the figure, if a deviation occurs in the distance along the optical axis between the image sensor 152 and the pattern plate 153, the projection area of ​​the reference pattern 210 may become larger than the imaging area 200 and protrude, or the projection area of ​​the reference pattern 210 may become smaller than the imaging area 200. In such cases, the positional deviation can be corrected by adjusting the number and / or thickness of the shims 156.

[0048] It should be noted that the offset between the imaging region 200 and the reference pattern 210 in the in-plane directions (X and Y directions) can be corrected by adjusting the position of the image sensor 152 relative to the housing 155.

[0049] [How to adjust the optical module] 10 is a flowchart for explaining a method for adjusting the optical module 150 in the three-dimensional scanner 10. This adjustment method is performed by an operator when assembling the optical module 150. During the adjustment, the operator performs the adjustment while observing the projection pattern with the image sensor 152.

[0050] Referring to Figure 10, in step (hereinafter, step will be abbreviated as "S") 110, the operator determines the deviation in distance between the pattern plate 153 and the beam splitter 151 from the reference pattern 210 of the pattern plate 153 projected onto the image sensor 152 and the pixels of the imaging area 200 of the image sensor 152.

[0051] Then, based on the determination result of S110, the worker determines the number / thickness of flat plate members in shim 156 for correcting the misalignment (S120), and adjusts adjustment shim 156 (S130). Specifically, if the projection area of ​​the reference pattern is larger than the imaging area of ​​image sensor 152, the worker adjusts shim 156 so as to move pattern plate 153 closer to beam splitter 151, and if the projection area is smaller than the imaging area, the worker adjusts shim 156 so as to move pattern plate 153 farther from beam splitter 151. The worker repeats the steps of S110 to S130 until the size of the projection range of the reference pattern matches the size of the imaging area.

[0052] After the deviation in the distance between pattern plate 153 and beam splitter 151 is corrected by adjusting shim 156, the operator then detects in S140 the positional deviation of pattern plate 153 in the rotational direction around the optical axis from reference pattern 210 and imaging area 200. Then, based on the detection result in S140, the operator adjusts the angle of pattern plate 153 and fixes pattern plate 153 to housing 155 using fastening member 158 (S150).

[0053] As described above, by configuring the optical module using adjustment shims and a rotatable pattern plate holder and adjusting the position of the pattern plate using the adjustment method shown in Fig. 10, it is possible to reduce deviations from the designed positions in terms of the relative positions and relative angles between the components in the optical module. This makes it possible to prevent a decrease in measurement accuracy in the three-dimensional scanner.

[0054] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0055] 10 three-dimensional scanner, 20 control device, 30 power supply, 40 display, 100 handpiece, 110 probe, 120 main body, 130 substrate, 140 light source, 141 light-emitting element, 142 light source lens, 150 optical module, 151 beam splitter, 152 image sensor, 153 pattern plate, 154 holder, 155 housing, 156 shim, 158 fastening member, 160 objective optical system, 161 lens, 162 focusing lens, 170 mirror, 200 imaging area, 210 reference pattern, 1541 circular portion, 1542 through hole, 1551 recess, 1552 guide portion, 1554 opening, 1561 to 1563 flat plate member.

Claims

1. An optical module used in a three-dimensional scanner that acquires three-dimensional shape information of an object using a focusing method with light from a light source, a sensor that detects light from the light source reflected by the object; a beam splitter that separates an optical path from the light source to the object and an optical path from the object to the sensor; a pattern plate disposed between the light source and the beam splitter and configured to project a reference pattern onto the sensor using light from the light source; a housing in which the sensor, the beam splitter, and the pattern plate are disposed; a shim disposed in the housing between the pattern plate and the beam splitter for adjusting a distance between the pattern plate and the beam splitter; the housing has a recess for disposing the pattern plate; The pattern plate is supported in the recess so as to be rotatable within a predetermined angular range around the optical axis of the light from the light source.

2. Further comprising a holder for holding the pattern plate; the pattern plate is placed in the recess while being held by the holder; The optical module according to claim 1 , wherein the shim is disposed between a bottom surface of the recess and the holder.

3. The pattern plate has a substantially square flat plate shape, 3. The optical module according to claim 2, wherein the outer shape of the holder is a combination of a square and a circle whose centers coincide with each other.

4. 4. The optical module according to claim 3, wherein an inner wall of the recess in the housing has a guide portion formed in an arc shape so as to guide a circular portion of the outer shape of the holder.

5. the shim includes at least one flat plate member; 5. The optical module according to claim 1, wherein the thickness of the at least one flat plate member is one of 0.05 mm, 0.10 mm, and 0.15 mm.

6. 6. The optical module according to claim 5, wherein the base material of the at least one flat plate member is stainless steel or aluminum.

7. the light source; an optical module according to any one of claims 1 to 4; an objective optical system configured to direct light from the light source that has passed through the optical module to the object, and to direct light reflected by the object to the optical module.

8. A method for adjusting a three-dimensional scanner that acquires three-dimensional shape information of an object using a focusing method, comprising: The three-dimensional scanner a light source that irradiates the object with light; an optical module disposed on an optical axis from the light source to the object; The optical module includes: a sensor that detects light from the light source reflected by the object; a beam splitter that splits light from the light source into two paths to the object and the sensor; a pattern plate disposed between the light source and the beam splitter and configured to project a reference pattern onto the sensor using light from the light source; a housing in which the sensor, the beam splitter, and the pattern plate are disposed; a shim disposed in the housing between the pattern plate and the beam splitter for adjusting a distance between the pattern plate and the beam splitter; the sensor is an imaging sensor; the shim includes one or more flat plate members; The adjustment method includes: determining whether the distance between the pattern plate and the beam splitter is within a predetermined range based on the image of the reference pattern projected onto the sensor and an imaging area of ​​the sensor; determining the number of the flat plate members to be used in the shim based on the result of the determining step; detecting a positional deviation of the pattern plate in the housing in a rotational direction around the optical axis based on an image of the reference pattern projected onto the sensor and an imaging area of ​​the sensor; and adjusting the position of the pattern plate based on the result of the detecting step.

Images