Thin film property measurement apparatus

Abstract

A thin film characteristic measuring device is disclosed for measuring the thickness or width of a thin film on an object to be inspected. The device includes a light source, a first reflector, a first actuator, and a lens assembly. The lens assembly is configured such that the angle formed by the optical axis and the principal ray of light transmitted through the lens assembly is less than or equal to the angle formed by the optical axis and the principal ray of light incident on the lens assembly. The light source may include a superluminescent diode (SLD). The device and method provide a thin film characteristic measuring apparatus that allows light transmitted through the lens assembly to reciprocate on the incident surface of the object to be inspected, while the first reflector repeatedly tilts within a predetermined angle range, thus enabling accurate measurement of relatively large areas and allowing for different control of the measured position.

Description

Technical Field

[0001] The present invention is a device for measuring the properties of a thin film of an object by using the interference phenomenon between the wavelengths of reflected light after it has been irradiated onto the object. Background Technology

[0002] In optical discs, semiconductors, batteries, and various displays, thin films that make up each of these are formed, and during their manufacturing process, it is necessary to measure the thickness and refractive index of the films.

[0003] The thickness and refractive index of thin films can be measured using reflectance measurement methods, and reflectometers can be used in thin film layer measurement systems. Reflectometers are non-contact, non-destructive measurement devices that can measure the properties of multilayer thin films and have the advantage of being able to perform measurements without special preparation or treatment of the object.

[0004] In this regard, U.S. Patent No. 7,286,242B2 (hereinafter referred to as "Prior Document") discloses an apparatus and a method for measuring the properties of thin films by means of a two-dimensional detector.

[0005] The thickness of the thin film can be measured on a sample substrate made of a substrate and a thin film using equipment according to existing literature.

[0006] Light rays from the light source pass through a beam splitter and lens 26 and are incident on a substrate with a thin film.

[0007] Of the light incident on the sample substrate, some light is reflected from the surface of the thin film, and another part can be reflected at the boundary between the substrate and the thin film after passing through the film, and the two reflected light rays have different optical paths.

[0008] Thus, the light reflected from different surfaces of the sample substrate has different optical paths, and interference occurs due to these differences. Furthermore, the optical paths differ for each wavelength, resulting in constructive or destructive interference depending on the wavelength of the light beam.

[0009] Light reflected from the sample substrate is projected onto a beam splitter, which analyzes the projected reflected light to obtain the intensity of the reflected light as a function of the wavelength. The results are then processed by a digital converter and an information processor to calculate the thickness, refractive index, and other parameters of the thin film on the sample substrate to obtain measurement values.

[0010] However, given the existing equipment and methods, since thickness measurements can only be performed at any point on the sample substrate, there is a need to develop a thin film characteristic measurement device that can adjust the position, method, etc. of the measurement differently. Summary of the Invention

[0011] Technical issues

[0012] The objective of this invention is to provide a thin film characteristic measuring device that can effectively and accurately measure the thickness and / or width of a thin film in an area exceeding the size (diameter) of the light irradiated onto the object.

[0013] Another objective of this invention is to provide a thin film property measuring device in which light irradiating an object is repeatedly deformed at its position and is incident and reflected in a direction perpendicular to the surface of the object.

[0014] Another objective of this invention is to provide a thin film property measuring device that can effectively measure the thin film of an object having a curved surface.

[0015] Another objective of this invention is to provide a thin film characteristic measuring device that can simultaneously measure several parts of an object.

[0016] Solution to the problem

[0017] The thin film property measuring device according to an embodiment of the present invention is a device for measuring the thickness and / or width of a thin film of an object.

[0018] The thin film property measurement device includes a light source, a first reflector, a first actuator, and a lens assembly.

[0019] The light source can be constructed from a superluminescent diode (SLD).

[0020] The first reflecting mirror reflects the light emitted from the light source.

[0021] The first actuator causes the first reflector to reciprocate and tilt within a predetermined angle range.

[0022] The lens assembly includes multiple lenses and is configured such that light reflected by the first mirror is incident and transmitted.

[0023] The lens assembly is configured such that the angle between the main beam of light transmitted through the lens assembly and the optical axis of the lens assembly is equal to or less than the angle between the main beam of light incident on the lens assembly and the optical axis of the lens assembly.

[0024] The thin film property measurement device can be configured such that when the angle between the principal ray of the light incident on the lens assembly and the optical axis is 0° to 3.7°, the angle between the principal ray of the light transmitted through the lens assembly and the optical axis is 0° to 0.1°.

[0025] The light emitted from the light source can have a center wavelength of 800 to 900 nm and a bandwidth of 100 to 200 nm.

[0026] The light source may include optical fibers that transmit light.

[0027] Optical fibers can have a diameter of 10 μm or less and a numerical aperture (NA) of 0.3 or less.

[0028] The thin film property measurement device may also include a collimator positioned between the light source and the first reflector.

[0029] The numerical aperture (NA) of the collimator is greater than that of the optical fiber.

[0030] The size (diameter) of the light rays passing through the collimator is 50 to 200 μm.

[0031] In a thin film property measurement device, the angle between the principal rays of light incident on the lens assembly can be controlled by a first actuator.

[0032] The center of the first reflecting mirror can be located on the extension line of the optical axis of the lens assembly.

[0033] The thin film property measuring device may also include: a second mirror that reflects the light reflected by the first mirror; and a second actuator that causes the second mirror to reciprocate and tilt within a predetermined angle range.

[0034] In a thin film property measurement device, light reflected by a second mirror can be incident on a lens assembly.

[0035] The thin film property measuring device may further include: a first transparent plate through which light irradiated by a light source is transmitted; a third actuator that causes the first transparent plate to reciprocate and tilt within a predetermined angle range; a second transparent plate through which light transmitted through the first transparent plate is transmitted; and a fourth actuator that causes the second transparent plate to reciprocate and tilt within a predetermined angle range.

[0036] The tilt axis of the first transparent plate and the tilt axis of the second transparent plate can be different from each other.

[0037] Light transmitted through the second transparent plate can be refracted by the first and second reflecting mirrors and then incident on the lens assembly.

[0038] The lens assembly may include a first lens, a second lens, a third lens, a fourth lens, and a fifth lens.

[0039] The first lens is constructed from a diverging lens.

[0040] The second lens is positioned behind the first lens and is constructed from a converging lens.

[0041] The third lens is positioned in front of the first lens and is constructed from a converging lens.

[0042] The fourth lens is positioned between the third lens and the first lens and is constructed as a converging lens.

[0043] The fifth lens is positioned between the third lens and the first lens and is constructed as a diverging lens.

[0044] The lens assembly may also include a sixth lens.

[0045] The sixth lens is positioned between the fifth lens and the first lens and is constructed as a converging lens.

[0046] The fourth lens can be placed in front of the fifth lens.

[0047] FL1, which is the sum of the focal lengths of the third, fourth, fifth, and sixth lenses, can be shorter than FL2, which is the sum of the focal lengths of the third, fourth, fifth, sixth, and first lenses.

[0048] The focal length FL3 of the second lens 72 can be longer than FL1 and shorter than FL2.

[0049] In a thin film property measurement device, when the diameter of the area formed by light rays incident on the third lens parallel to the optical axis of the lens assembly is D1, the diameter of the area formed when the light rays transmitted through the lens assembly contact the surface of the object is D2. The sum of the focal lengths of the third, fourth, fifth, sixth, and first lenses is FL2, and the focal length of the second lens is FL3. The value of FL3 / FL2 can be within ±10% of the value of D2 / D1.

[0050] In a thin film property measurement device, when the distance between the first reflector and the third lens is L1, and the distance between the second lens and the object is L2, L1 and L2 can be 20 mm or larger, and the effective focal length of the lens assembly can be 85 mm.

[0051] The first lens can be an asymmetric biconcave lens.

[0052] The second lens can be a plano-convex lens.

[0053] The third lens can be a positive meniscus lens.

[0054] The fourth lens can be an asymmetric biconvex lens.

[0055] The fifth lens can be a plano-concave lens.

[0056] The sixth lens can be an asymmetric biconvex lens.

[0057] The thin film characteristic measurement device may include: a collimator positioned between a light source and a first reflector; and a housing, a lens assembly and a first actuator fixed to the housing, the housing opening toward the collimator.

[0058] Multiple heat dissipation fins can be formed in the first actuator.

[0059] Thin film property measurement equipment may also include diffractive optical elements positioned between the light source and the lens assembly.

[0060] Beneficial effects of the present invention

[0061] A thin-film characteristic measuring device according to an embodiment of the present invention includes a light source, a first reflector, a first actuator, and a lens assembly. The light source illuminates light, the first actuator causes the first reflector to reciprocate and tilt within a predetermined angle range, and the light reflected by the first reflector is incident on the lens assembly and transmitted toward an object. The lens assembly is configured such that the angle between the main beam of light transmitted through the lens assembly and the optical axis of the lens assembly is equal to or less than the angle between the main beam of light incident on the lens assembly and the optical axis of the lens assembly. Therefore, a thin-film characteristic measuring device can be provided in which light can be incident and reflected toward an object at various different points in a predetermined segment or region, and in this case, the light rays at corresponding points can be kept parallel to each other, and the area, zone, or method to be inspected can be adjusted differently.

[0062] Furthermore, the thin film characteristic measuring device according to an embodiment of the present invention is configured to include a first reflector, a first actuator, and a lens assembly, and as a result, light irradiated onto the object can be incident and reflected in a direction perpendicular to the surface of the object, while being repeatedly deformed at its position, and the thickness and / or width of the thin film of the object can be measured effectively and accurately.

[0063] The thin film characteristic measuring device according to an embodiment of the present invention can be configured to include a first transparent plate, a third actuator, a second transparent plate, and a fourth actuator. As a result, the position of the light incident on the object can be effectively converted, and further, the angle of the light incident on the object can be effectively converted, and the thin film of an object having a curved surface can be effectively measured by the thin film characteristic measuring device according to an embodiment of the present invention.

[0064] The thin film property measuring device according to an embodiment of the present invention can be configured to further include a diffractive optical element positioned between the light source and the lens assembly. Such a thin film property measuring device can be provided in which light incident on the lens assembly can be split into several rays by a refractive element and then incident on the lens assembly, resulting in the simultaneous measurement of several parts of the object. Attached Figure Description

[0065] Figure 1 and Figure 2 These are schematic diagrams illustrating the thin film property measurement device and the movement of light within it. Figure 1 and Figure 2 In the image, the lens assembly is shown in cross-sectional shape, and the housing is represented by dashed lines.

[0066] Figure 3a It is a schematic diagram showing the cross-section of the lens constituting the lens assembly and the light rays incident on and transmitted to the lens assembly along the optical axis of the lens assembly.

[0067] Figure 3b and Figure 3c Each of them is shown schematically in Figure 3a A diagram showing the incident and transmitted light rays on and to the lens assembly at points (off-axis) that are spaced apart from the optical axis of the lens assembly.

[0068] Figure 4 This is a schematic diagram showing some components of a thin film property measurement device and the light rays transmitted through and reflected off the components.

[0069] Figure 5 This shows the first and second reflecting mirrors in... Figure 4 A diagram showing the tilted state of the thin film property measurement device.

[0070] Figure 6 It shows the light transmitted through the lens assembly according to... Figure 4 and Figure 5 The diagram shows the different states of the first and second reflectors traveling in the thin film property measurement device depending on their tilt.

[0071] Figure 7 This shows the first and second transparent plates in... Figure 4 A diagram showing the tilted state of the thin film property measurement device.

[0072] Figure 8 It shows the light transmitted through the lens assembly according to... Figure 4 and Figure 7 The diagram shows the different states of the first and second transparent plates traveling in the thin film property measurement device, depending on the degree of tilt.

[0073] Figure 9a , Figure 9b and Figure 9c Each of these is a diagram schematically illustrating the state of light movement with a refractive element.

[0074] Figure 10This is a schematic diagram illustrating the inspection of an object's condition using a thin-film property measurement device.

[0075] Figure 11 It is shown schematically. Figure 10 A diagram of the cross-section of the object and the light rays incident on and reflected from the object.

[0076] Figure 12a It is a graph showing the position of light incident on the object over time in the thin film property measuring device according to the embodiment. Figure 12b It is a consideration Figure 12a The curve graph shows the movement of objects, and Figure 12c It is a diagram showing the light rays incident on the surface of an object.

[0077] Figure 13a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 13b It is a consideration Figure 13a The curve graph shows the movement of objects, and Figure 13c It is a diagram showing the light rays incident on the surface of an object.

[0078] Figure 14a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 14b It is a consideration Figure 14a The curve graph shows the movement of objects, and Figure 14c It is a diagram showing the light rays incident on the surface of an object.

[0079] Figure 15a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 15b It is a consideration Figure 15a The curve graph shows the movement of objects, and Figure 15c It is a diagram showing the light rays incident on the surface of an object.

[0080] Figure 16a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 16b It is a consideration Figure 16a The curve graph shows the movement of objects, and Figure 16c It is a diagram showing the light rays incident on the surface of an object. Detailed Implementation

[0081] In the following description, embodiments of the invention will be described in more detail with reference to the accompanying drawings. Throughout the detailed description, the same reference numerals refer to the same elements.

[0082] Figure 1 and Figure 2 The diagrams schematically illustrate the movement of the thin film property measuring device 1 and the light rays R, R1, and R2 within the thin film property measuring device 1.

[0083] Figure 3a This is a schematic diagram showing the cross-section of the lens constituting the lens assembly 70 and the light rays incident on and transmitted to the lens assembly 70 along the optical axis OA of the lens assembly 70.

[0084] Figure 3b and Figure 3c Each of them is shown schematically in Figure 3a A diagram showing the light rays incident on and transmitted to the lens assembly 70 at points (off-axis) spaced apart from the optical axis OA of the lens assembly 70.

[0085] The measuring device 1 according to an embodiment of the present invention is a device for measuring the thickness and / or width of a thin film of an object.

[0086] The measuring device 1 (hereinafter referred to as the thin film property measuring device 1') is configured to include a light source 10, a first reflector 30, a first actuator 35 and a lens assembly 70.

[0087] Light rays R1 incident on lens assembly 70 and light rays R2 transmitted through lens assembly 70 are incident on the surface of the object. The light rays reflected from the object can be incident on lens assembly 70 again (incident at the outlet 70c of lens assembly 70), and the light rays reflected from the object are analyzed by a separate device, and as a result, the thickness, refractive index, etc. of the thin film constituting the object can be calculated.

[0088] The light source 10 is configured to emit light with high brightness and wide bandwidth.

[0089] The light source 10 can be configured to include a superluminescent diode (SLD). Here, the superluminescent diode can also be referred to as a "superluminescent laser diode".

[0090] Superluminescent diodes (or superluminescent laser diodes) combine the advantages of laser diodes with the characteristics of LEDs. Superluminescent diodes can possess characteristics such as ultra-small size, low power consumption, high efficiency, high brightness, and high interconnectivity with optical fibers—advantages of laser diodes—while also exhibiting the low coherence characteristic of LEDs.

[0091] The light emitted from the light source 10 can have a bandwidth of 5nm to 700nm.

[0092] In an embodiment, the light emitted from the light source 10 may have a center wavelength of 400 nm or greater and a bandwidth of 40 nm or greater.

[0093] In another embodiment, the light source 10 may have a center wavelength of 100 to 1000 nm and a bandwidth of 400 to 2000 nm for the light emitted from the light source 10.

[0094] In another embodiment, the light source 10 may have a center wavelength of 800 to 900 nm and a bandwidth of 100 to 200 nm for the light emitted from the light source 10. More specifically, the light source 10 may have a center wavelength of 850 nm and a bandwidth of 165 nm ± 82.5 nm for the light emitted from the light source 10.

[0095] The light source 10 may include an optical fiber 11 for emitting light.

[0096] Fiber 11 may have a diameter of 10 μm or less and a numerical aperture (NA) of 0.3 or less. Fiber 11 may have a diameter of 5 μm or less and a numerical aperture (NA) of 0.14.

[0097] The first reflecting mirror 30, made of a mirror, is configured to reflect the light R emitted from the light source 10.

[0098] The first actuator 35 is configured to reciprocate and tilt the first reflector 30 within a predetermined angular range. The first actuator 35 may be configured to include an electric motor and may be configured to include a stepper motor.

[0099] The first reflector 30 is connected to the drive shaft (rotation shaft 35a) of the first actuator 35 including the motor, and the first reflector 30 can be tilted back and forth within a predetermined angle range when the drive shaft (rotation shaft 35a) of the first actuator 35 rotates repeatedly in two directions.

[0100] The rotational speed and rotational angle range of the drive shaft (rotation shaft 35a) of the first actuator 35 can be changed in different ways.

[0101] The first reflector 30 and the first actuator 35 can be formed by a galvanometer scanner. That is, the first reflector 30 can be configured as a mirror constituting a galvanometer scanner, and the first actuator 35 can be configured as a motor constituting a galvanometer scanner.

[0102] The lens assembly 70 is configured to include a plurality of lenses 71, 72, 73, 74, 75 and 76.

[0103] The lens assembly 70 is configured to include a lens body 70a to which a plurality of lenses are fixed. The lens body 70a may be formed in a tubular shape or in a circular tubular shape.

[0104] The inlet 70b and the outlet 70c of the lens assembly 70 are respectively formed at both ends of the lens body 70a.

[0105] The inlet 70b of the lens assembly 70 is an opening facing the first reflecting mirror 30, and the outlet 70c of the lens assembly 70 is an object-oriented opening.

[0106] Light rays R1 incident on the inlet 70b of the lens assembly 70 can be transmitted through the lens assembly 70 and then exit to the outlet 70c (R2), and light rays incident on the outlet 70c of the lens assembly 70 can be transmitted through the lens assembly 70 and then exit to the inlet 70b.

[0107] When describing the “direction” of the lens assembly 70 according to an embodiment of the present invention, the inlet 70b of the lens assembly 70 is set to the front of the lens assembly, and the outlet 70c of the lens assembly 70 is set to the rear of the lens assembly.

[0108] The light ray R1 reflected by the first reflecting mirror 30 is incident in front of the lens assembly 70 and transmitted to the rear (the rear side of the incident side).

[0109] The optical axis OA of the lens assembly 70 can be set to be perpendicular to the surface of the object.

[0110] The light ray R1 reflected by the first reflecting mirror 30 can be incident on the lens assembly 70 as an optical axis OA parallel to the lens assembly 70, and transmitted (R2) as an optical axis OA parallel to the lens assembly 70 (see...). Figure 1 and Figure 3a ).

[0111] The light ray R1 reflected by the first reflecting mirror 30 can be incident on the lens assembly 70, and is tilted with the optical axis OA of the lens assembly 70, and is transmitted (R2) parallel to the optical axis OA of the lens assembly 70 (see Figure 3a ).

[0112] Lens assembly 70 can be configured such that the angle between the principal ray of the transmitted light ray R2 passing through the exit 70c of lens assembly 70 and the optical axis OA of lens assembly 70 is equal to or less than the angle between the principal ray of the incident light ray R1 incident into the entrance 70b of lens assembly 70 and the optical axis OA of lens assembly 70 (see [link to documentation]). Figure 3a ).

[0113] When describing embodiments of the present invention, "transmitted light" may or may not be refracted while passing through a lens or the like. Transmitted light can be refracted light.

[0114] In one embodiment, the thin film property measuring device 1 can be configured such that when the angle between the principal ray of R1 incident on the inlet 70b of the lens assembly 70 and the optical axis OA is 0 to 3.7°, the angle between the principal ray of R2 transmitted through each lens of the lens assembly 70 and exiting to the outlet 70c of the lens assembly 70 and the optical axis OA is 0 to 0.1°. When the angle between the principal ray of R1 incident on the inlet 70b of the lens assembly 70 and the optical axis OA is 0°, the angle between the principal ray of R2 transmitted through the outlet 70c of the lens assembly 70 and the optical axis OA can be 0°, and when the angle between the principal ray of R1 incident on the inlet 70b of the lens assembly 70 and the optical axis OA is 3.7°, the angle between the principal ray of R2 transmitted through the outlet 70c of the lens assembly 70 and the optical axis OA can be 0.1° (see [link to documentation]). Figure 3a ).

[0115] The thin film property measuring device 1 can be configured to also include a collimator 20 positioned between the light source 10 and the first reflecting mirror 30. The collimator is an optical device used to form parallel light rays.

[0116] The numerical aperture (NA) of the collimator 20 can be configured to be larger than the NA of the optical fiber 11 constituting the light source 10. In an embodiment, the NA of the collimator 20 can be configured to be 0.51.

[0117] In the thin film property measuring device 1 according to an embodiment of the present invention, the size (diameter) of the light passing through the collimator 20 can be configured to be 50 to 200 μm.

[0118] The thin film property measuring device 1 can be configured such that the angle between the principal ray of the light ray R1 incident on the lens assembly 70 and the optical axis OA is controlled by the first actuator 35.

[0119] The center of the first reflecting mirror 30 can be positioned on the extension line of the optical axis OA of the lens assembly 70. Light rays from the light source 10 can pass through the collimator 20, then be reflected at the center of the first reflecting mirror 30, and can be incident on the entrance 70b of the lens assembly 70 along the same line as the optical axis OA. That is, the light ray R1 reflected by the first reflecting mirror 30 can be incident on the center of the lens assembly 70 in a direction perpendicular to the entrance 70b (incident angle of 0°). In this case, the light ray R2 transmitted through the exit 70c can be incident on the surface of the object along the same line as the optical axis OA of the lens assembly 70 (transmission angle of 0°).

[0120] Furthermore, when the first reflecting mirror 30 is tilted within a predetermined angle range, the light ray R1 reflected by the first reflecting mirror 30 is incident on the lens assembly 70, and the angle is deformed within a predetermined angle range with respect to the optical axis OA of the lens assembly 70 (e.g., the incident angle is deformed between 0° and 3.7°). In this case, the light ray R2 transmitted through the exit 70c can be incident on the surface of the object at a point spaced apart from the optical axis OA in a direction substantially parallel to the optical axis OA of the lens assembly 70. That is, it can be identified that the angle between the principal ray R2 transmitted through each lens of the lens assembly 70 and then exiting to the exit 70c of the lens assembly 70 and the optical axis OA is even smaller than the angle between the principal ray of R1 incident on the entrance 70b of the lens assembly 70 and the optical axis OA (when the incident angle is 0 to 3.7°, the transmission angle is configured to be 0 to 0.1°) (see Figure 3a ).

[0121] Thus, in the thin film property measuring device 1 according to an embodiment of the present invention, the position of the light rays incident on the object can be easily changed by the first reflector 30 and the first actuator 35, and in this case, all the light rays incident on the object can be incident perpendicular to or substantially perpendicular to the surface of the object.

[0122] The thin film property measurement device 1 can be configured to also include a second reflector 40 and a second actuator 45 (see Figure 2 ).

[0123] The second reflecting mirror 40, made of a mirror, is configured to reflect the light reflected by the first reflecting mirror 30. The light R emanating from the light source 10 passes through the collimator 20 and is then reflected in turn by the first reflecting mirror 30 and the second reflecting mirror 40 to be incident on the lens assembly 70.

[0124] The second actuator 45 is configured to reciprocate and tilt the second reflector 40 within a predetermined angular range. The second actuator 45 may be configured to include an electric motor and may be configured to include a stepper motor.

[0125] The second reflector 40 can be connected to the drive shaft (rotation shaft 45a) of the second actuator 45 configured to include a motor, and the second reflector 40 can be tilted back and forth within a predetermined angle range when the drive shaft (rotation shaft 45a) of the second actuator 45 rotates repeatedly in both directions.

[0126] The rotational speed and rotational angle range of the drive shaft (rotation shaft 45a) of the second actuator 45 can be changed in different ways.

[0127] The second reflector 40 and the second actuator 45 can be formed from a galvanometer scanner. That is, the second reflector 40 can be configured as a mirror constituting a galvanometer scanner, and the second actuator 45 can be configured as a motor constituting a galvanometer scanner.

[0128] In the thin film property measuring device 1 according to an embodiment of the present invention, the first reflector 30 and the first actuator 35 can constitute any galvanometer scanner, and the second reflector 40 and the second reflector 40 can constitute another galvanometer scanner.

[0129] The tilt axis of the first reflector 30 (drive shaft 35a of the first actuator 35) and the tilt axis of the second reflector 40 (drive shaft 45a of the second actuator 45) can be configured to be parallel to each other or to be non-parallel to each other.

[0130] Figure 4 This is a schematic diagram showing some components of the thin film property measuring device 1, as well as the light rays R, R1, and R2 that are transmitted through the components and reflected on them.

[0131] Figure 5 This shows the first reflecting mirror 30 and the second reflecting mirror 40 in... Figure 4 A diagram showing the tilted state of the thin film property measuring device 1.

[0132] Figure 6 Each of (a), (b), (c), (d), (e), and (f) illustrates the light transmitted through the lens assembly according to the first reflecting mirror 30 and the second reflecting mirror 40. Figure 4 and Figure 5 The diagram shows the different states of travel in the thin film property measuring device 1 depending on the degree of tilt.

[0133] Figure 7 This shows the first transparent plate 50 and the second transparent plate 60 in... Figure 4 A diagram showing the tilted state of the thin film property measuring device 1.

[0134] Figure 8 Each of (a), (b), (c), (d), (e), and (f) illustrates the light transmitted through the lens assembly according to the first transparent plate 50 and the second transparent plate 60. Figure 4 and Figure 7 The diagram shows the different states of travel in the thin film property measuring device 1 depending on the degree of tilt.

[0135] The thin film property measuring device according to an embodiment of the present invention can be configured to include a first transparent plate 50, a third actuator 55, a second transparent plate 60, and a fourth actuator 65.

[0136] The first transparent plate 50 is formed in the form of a transparent plate. The first transparent plate 50 may be made of transparent glass.

[0137] The light R emitted from the light source 10 can be transmitted through the first transparent plate 50.

[0138] Light rays from the light source 10 can pass through the collimator 20 and then be transmitted through the first transparent plate 50.

[0139] The third actuator 55 is configured to cause the first transparent plate 50 to reciprocate and tilt within a predetermined angle range. The third actuator 55 may be configured to include an electric motor and may be configured to include a stepper motor.

[0140] The first transparent plate 50 can be connected to the drive shaft (rotation shaft 55a) of the third actuator 55, which is configured to include a motor, and the first transparent plate 50 can be tilted back and forth within a predetermined angle range when the drive shaft (rotation shaft 55a) of the third actuator 55 rotates repeatedly in two directions.

[0141] The rotational speed and rotational angle range of the drive shaft (rotation shaft 55a) of the third actuator 55 can be changed in different ways.

[0142] The second transparent plate 60 is formed in the form of a transparent plate. The second transparent plate 60 may be made of transparent glass.

[0143] Light rays that have been transmitted through the first transparent plate 50 may be incident on the second transparent plate 60 and then transmitted through the second transparent plate 60.

[0144] Light rays transmitted through the second transparent plate 60 can be incident on the first reflecting mirror 30.

[0145] The fourth actuator 65 is configured to reciprocate and tilt the second transparent plate 60 within a predetermined angle range. The fourth actuator 65 may be configured to include an electric motor and may be configured to include a stepper motor.

[0146] The second transparent plate 60 can be connected to the drive shaft (rotation shaft 65a) of the fourth actuator 65, which is configured to include a motor, and the second transparent plate 60 can be tilted back and forth within a predetermined angle range when the drive shaft (rotation shaft 65a) of the fourth actuator 65 rotates repeatedly in both directions.

[0147] The rotational speed and rotational angle range of the drive shaft (rotation shaft 65a) of the fourth actuator 65 can be changed in different ways.

[0148] The tilting axis of the first transparent plate 50 (drive shaft 55a of the third actuator 55) and the tilting axis of the second transparent plate 60 (drive shaft 65a of the fourth actuator 65) can be configured to be parallel to each other or to be non-parallel to each other.

[0149] In the thin film property measurement device 1, light rays that are transmitted sequentially through the first transparent plate 50 and the second transparent plate 60 can be configured to be refracted by the first reflecting mirror 30 and the second reflecting mirror 40, and then incident on the lens assembly 70.

[0150] Adjusting the tilt angle of the first transparent plate 50 and the second transparent plate 60 can change the position of the light incident on the first reflector 30.

[0151] According to an embodiment of the present invention, the thin film property measuring device 1 adjusts the tilt angles of the first transparent plate 50 and the second transparent plate 60 and / or the tilt angles of the first reflector 30 and the second reflector 40 to adjust the angle and position of the light ray R1 incident on the lens assembly 70 and the angle and position of the light ray R2 transmitted through the lens assembly 70 and incident on the object.

[0152] In one embodiment, the tilt angles of the first reflector 30 and the second reflector 40 are adjusted, and as a result, the light ray R2 transmitted through the lens assembly 70 and then incident on the object can be spaced apart from the optical axis OA of the lens assembly 70. In this case, the light ray R2 transmitted through the lens assembly 70 and then incident on the object can be configured to be substantially parallel to the optical axis OA of the lens assembly 70.

[0153] Figure 6 (a), (b), (c), (d), (e), and (f) show the different travels of the light ray R2 transmitted through the lens assembly 70 and then incident on the object when the tilt (angle) of the first reflector 30 and the second reflector 40 are adjusted differently.

[0154] In this way, the light ray R2 transmitted through the lens assembly 70 and then incident on the object can be incident on the predetermined area A, and the tilt angles of the first reflector 30 and the second reflector 40 are adjusted differently to adjust the position of the light ray R2 incident on the area A.

[0155] As described above, several parts of an object can be inspected using the thin film characteristic measuring device 1 according to an embodiment of the present invention.

[0156] In another embodiment, by adjusting the tilt angles of the first transparent plate 50 and the second transparent plate 60, the light ray R2 transmitted through the lens assembly 70 can be configured to be incident on the object, while simultaneously tilting at points spaced apart from the optical axis OA of the lens assembly 70 (see [reference]). Figure 3b and Figure 3c ).

[0157] Figure 8(a), (b), (c), (d), (e), and (f) show the different travel of the light rays R2 transmitted through the lens assembly 70 and then incident on the object when the tilt (angle) of the first transparent plate 50 and the second transparent plate 60 are adjusted differently.

[0158] In this way, the light ray R2 transmitted through the lens assembly 70 and then incident on the object can be incident on the predetermined area A, and the tilt angles of the first transparent plate 50 and the second transparent plate 60 are adjusted differently to adjust the angle of the light ray R2 incident on the area A differently.

[0159] As described above, with the thin film property measuring device 1 according to an embodiment of the present invention, even when the surface of the object forms a convex curve, light can be incident in a direction perpendicular to the surface of the object.

[0160] The lens assembly 70 according to an embodiment of the present invention may be configured to include a first lens 71, a second lens 72, a third lens 73, a fourth lens 74, and a fifth lens 75.

[0161] The lens assembly 70 may be configured to also include a sixth lens 76.

[0162] The arrangement of the first lens 71 and the second lens 72 can be fixed, while the third lens 73, the fourth lens 74, the fifth lens 75 and the sixth lens 76 can be changed.

[0163] The first lens 71 is formed by a diverging lens. The first lens 71 is formed by an asymmetric biconcave lens.

[0164] The second lens 72 is positioned behind the first lens 71 and is formed by a converging lens. The second lens 72 may be formed by a plano-convex lens.

[0165] The third lens 73 is positioned in front of the first lens 71 and is formed by a converging lens. The third lens 73 is formed by a positive meniscus lens.

[0166] The fourth lens 74 is disposed between the third lens 73 and the first lens 71, and is formed by a converging lens. The fourth lens 74 may be disposed in front of the fifth lens 75.

[0167] The fourth lens 74 is formed by an asymmetric biconvex lens.

[0168] The fifth lens 75 is disposed between the third lens 73 and the first lens 71, and is formed by a diverging lens. The fifth lens 75 may be formed by a plano-concave lens.

[0169] The sixth lens 76 is disposed between the fifth lens 75 and the first lens 71, and is formed by a converging lens. The sixth lens 76 is formed by an asymmetric biconvex lens.

[0170] FL1, which is the sum of the focal lengths of the third lens 73, the fourth lens 74, the fifth lens 75, and the sixth lens 76, can be configured to be shorter than FL2, which is the sum of the focal lengths of the third lens 73, the fourth lens 74, the fifth lens 75, the sixth lens 76, and the first lens 71.

[0171] The focal length FL3 of the second lens 72 can be longer than FL1 and shorter than FL2.

[0172] In the thin film property measurement device 1, when the diameter of the first region A1, which is the area formed by light rays incident on the third lens 73 parallel to the optical axis OA of the lens assembly 70, is D1, and the diameter of the second region A2, which is the area formed by light rays transmitted through the lens assembly 70 and touching the surface of the object, is D2, the FL3 / FL2 value can be within ±10% of the D2 / D1 value (see [reference]). Figures 3a to 3c ).

[0173] In the thin film property measurement device 1, when the distance between the first reflector 30 and the third lens 73 is L1 and the distance between the second lens 72 and the object is L2, L1 and L2 can be 20 mm or larger, and the effective focal length of the lens assembly 70 can be 85 mm.

[0174] Each of L1 and L2 can be formed to be 20mm.

[0175] The length from the third lens 73 to the second lens 72 in the lens assembly 70 can be 89 mm.

[0176] When the light ray R1 reflected by the first reflecting mirror 30 is incident on the lens assembly 70, the center of the first reflecting mirror 30 and the center of the first region A1 can coincide with each other.

[0177] When the light ray R2 reflected by the second reflector 40 is incident on the lens assembly 70, the center of the second reflector 40 and the center of the first region A1 can coincide with each other.

[0178] When light ray R1 is incident on lens assembly 70 from the center of first region A1, light ray R2, which is transmitted through lens assembly 70 and incident on second region A2, is perpendicular or substantially perpendicular to second region A2 (see [reference]). Figure 3a ).

[0179] When light ray R1 is incident on lens assembly 70 from a point off-axis from the center of the first region A1, the light ray transmitted through lens assembly 70 and incident on the second region A2 can form an angle of 0 to 20° with the optical axis OA of lens assembly 70.

[0180] For example, when light ray R1 is incident on lens assembly 70 from the edge of first region A1, light ray R2, which is transmitted through lens assembly 70 and incident on second region A2, is inclined to the optical axis OA of lens assembly 70. In this case, even if the principal ray R1 of the light rays incident on lens assembly 70 forms a different angle with the optical axis OA of lens assembly 70, the principal rays R2 of the light rays transmitted through lens assembly 70 and incident on second region are parallel or substantially parallel to each other (see [reference]). Figure 3b and Figure 3c ).

[0181] The thin film property measuring device 1 may include a housing 100.

[0182] The housing 100 can be formed in the shape of a box. The housing 100 can be made of a relatively rigid material. The housing 100 can be made of plastic, metal, etc.

[0183] The inlet 70b of the lens assembly 70 and the first actuator 35 can be fixed to the housing 100.

[0184] The first reflector 30 is housed in the housing 100, and the housing 100 includes an opening that opens toward the collimator 20.

[0185] When the thin film characteristic measuring device 1 includes a second reflector 40 and a second actuator 45, the second actuator 45 can also be fixed to the housing 100, and the second reflector 40 can be housed in the housing 100.

[0186] Multiple heat dissipation fins 36 may be formed on the first actuator 35. The heat dissipation fins 36 of the first actuator 35 may be made of a metal material with excellent thermal conductivity, and the multiple heat dissipation fins 36 of the first actuator 35 are spaced apart from each other.

[0187] Furthermore, multiple heat dissipation fins 46 may be formed on the second actuator 45. The heat dissipation fins 46 of the second actuator 45 may be made of a metal material with excellent thermal conductivity, and the multiple heat dissipation fins 46 of the second actuator 45 are spaced apart from each other.

[0188] Figure 9a , Figure 9b and Figure 9c Each of these is a diagram schematically showing the state of motion of light ray R with diffractive optical element 80.

[0189] The thin film property measuring device 1 may also include a diffractive optical element 80 positioned between the light source 10 and the lens assembly 70.

[0190] Light rays can branch into several rays when passing through a diffractive optical element 80.

[0191] In one embodiment, the light rays passing through the diffractive optical element 80 can be branched into 3x3 (9 rays), and in another embodiment, the light rays passing through the diffractive optical element 80 can be branched into 5x5 (25 rays).

[0192] When light rays pass through the diffractive optical element 80, the branched rays can be incident and emitted (transmitted) at different points on the lens assembly 70, and as a result, the light rays can be illuminated and measured (inspected) at several points on the object.

[0193] In the following, a method for measuring the thickness and width of a thin film constituting an object using a thin film property measuring device 1 according to an embodiment of the present invention will be described.

[0194] Figure 10 This is a schematic diagram showing the state of object 200 being checked using a thin film property measuring device 1.

[0195] Figure 11 It is shown schematically. Figure 10 A diagram of the cross section of object 200 and the light rays incident on and reflected from object 200.

[0196] Figure 12a It is a graph showing the position of light incident on the object over time in the thin film property measuring device according to the embodiment. Figure 12b It is a consideration Figure 12a The curve graph shows the movement of objects, and Figure 12c It is a diagram showing the light rays incident on the surface of an object.

[0197] Figure 13a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 13b It is a consideration Figure 13a The curve graph shows the movement of objects, and Figure 13c It is a diagram showing the light rays incident on the surface of an object.

[0198] Figure 14a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 14b It is a consideration Figure 14a The curve graph shows the movement of objects, and Figure 14c It is a diagram showing the light rays incident on the surface of an object.

[0199] Figure 15a It is a graph showing the position of light incident on an object over time in a thin film property measuring device according to another embodiment. Figure 15bIt is a consideration Figure 15a The curve graph shows the movement of objects, and Figure 15c It is a diagram showing the light rays incident on the surface of an object.

[0200] Figure 10 The X, Y, and Z directions indicated below are orthogonal to each other.

[0201] Object 200 may be a vehicle battery. Object 200 may be a part of the battery.

[0202] The battery constituting object 200 may include aluminum foil 210, active material 220 and insulating film 230.

[0203] Aluminum foil 210 can form a current collector with a positive electrode.

[0204] The active material 220 is laminated onto the aluminum foil 210.

[0205] An insulating film 230 is laminated onto an aluminum foil 210 and an active material 220, and the insulating film 230 is formed along the edge of the active material 220. The insulating film 230 may be made of polyvinylidene fluoride (PVDF).

[0206] The thin film characteristic measuring device 1 according to an embodiment of the present invention can be used to measure the thickness and width of the insulating film 230 in an object 200. When measuring the object 200, the object 200 can move in a direction X parallel to the longitudinal direction of the insulating film 230.

[0207] The characteristics of the reflected light R3 of the light ray R2 that is irradiated from the thin film property measuring device 1 and incident on the object 200 can vary depending on the position of the object, and the interference of the reflected light ray R3 can be shown differently. As a result, the characteristics of the reflected light ray R3 are determined to measure the width and thickness of the insulating film 230.

[0208] The tilt axis of the first reflecting mirror 30 can be placed parallel to the movement direction X of the object 200.

[0209] When the first reflecting mirror 30 tilts back and forth, the incident light ray R2 and the reflected light ray R2 on the object 200 move back and forth in the direction Y, which is orthogonal to the tilt axis of the first reflecting mirror 30 (M1).

[0210] Furthermore, as the first reflecting mirror 30 tilts back and forth, when the light ray R2 irradiated from the thin film characteristic measuring device 1 is represented by a point, the position of the point (hereinafter referred to as the point) changes according to time t. As a result, the position of point S can be represented as a curve according to time t.

[0211] A point S at time t can be formed by various waveforms (hereinafter referred to as the waveform of the point), and the wavelength, frequency, amplitude, etc. of each point waveform SW can be formed differently.

[0212] In this implementation, the point waveform SW can be formed in the form of a sine wave.

[0213] In another embodiment, the point waveform SW can be formed in the form of a triangular wave (see...). Figure 13a and Figure 14a ).

[0214] In another embodiment, the point waveform SW can be formed in the form of a square wave or a similar square wave (see [reference]). Figures 15a to 15c ).

[0215] Considering that object 200 moves in conjunction with other objects, that is, when object 200 moves, the point waveform SW on the surface of object 200 is shown in a form where the wavelength becomes approximately longer than the speed of movement of object 200 (see [reference]). Figure 12b , Figure 13b , Figure 14b , Figure 15b and Figure 16b ).

[0216] In this embodiment, the amplitude of the point waveform SW is relatively small, allowing each point to be positioned within the width of the insulating film 230 of the object 200. For example, when the expected width of the insulating film 230 is approximately 4 mm, the thin film characteristic measuring device 1 can be controlled so that the double value (peak to peak) of the point waveform SW becomes 1.2 mm. Furthermore, in this case, the relative position of the thin film characteristic measuring device 1 and the object 200 can be adjusted so that the point is located on the insulating film 230 of the object.

[0217] In another embodiment, the amplitude of the dot waveform SW is relatively large, allowing each dot to move beyond the insulating film 230 of the object and into the formation range of the aluminum foil 210 and the active material 220 (see [link]). Figure 14c For example, when the expected width of the insulating film 230 is about 4 mm, the thin film characteristic measuring device 1 can be controlled so that the dual values ​​(peak to peak) of the point waveform SW are 5.5 mm to 11 mm.

[0218] When the amplitude of the point waveform SW is relatively small, the tilting velocity (Hz) of the first reflector 30 can be faster compared to when the amplitude of the point waveform SW is relatively large. In an embodiment, when the amplitude of the point waveform SW is 5.5 mm, the tilting velocity (Hz) of the first reflector 30 can be 175 Hz, and when the amplitude of the point waveform SW is 1.2 mm, the tilting velocity (Hz) of the first reflector 30 can be 1 kHz.

[0219] Therefore, when it is necessary to quickly measure the thickness of the insulating film 230, the thin film characteristic measuring device 1 can be controlled so that the amplitude of the point waveform SW is relatively small.

[0220] Furthermore, when the thickness and width of the insulating film 230 are to be measured together, the thin film characteristic measuring device 1 can be controlled so that the amplitude of the point waveform SW is relatively large.

[0221] Specific embodiments of this disclosure have been described and illustrated above. However, the invention is not limited to the disclosed embodiments, and those skilled in the art will understand that these embodiments can be modified and transformed to other specific embodiments without departing from the spirit and scope of the invention. Therefore, the scope of the invention is not limited by the described embodiments, but by the technical spirit disclosed in the claims.

[0222] Industrial Applicability

[0223] According to an embodiment of the present invention, a thin film characteristic measuring device can be provided in which the light source is formed by a broadband laser light source, and when the first reflecting mirror is repeatedly tilted within a predetermined angle range, the light transmitted through the lens assembly can reciprocate on the incident surface of the object while remaining parallel to each other. As a result, the position, method, etc. to be measured can be adjusted differently, and there is significant industrial applicability.

Claims

1. A thin film characteristic measuring device, the thin film characteristic measuring device being used to measure the thickness or width of a thin film of an object, the thin film characteristic measuring device comprising: The light source is constructed from a superluminescent diode (SLD); A first reflecting mirror reflects light emitted from the light source; The first actuator causes the first reflector to reciprocate and tilt within a predetermined angle range; as well as A lens assembly comprising multiple lenses, wherein light reflected by the first reflecting mirror is incident on and transmitted through the lens assembly. The lens assembly is configured such that the angle between the principal ray of light transmitted through the lens assembly and the optical axis is equal to or less than the angle between the principal ray of light incident on the lens assembly from the optical axis and the optical axis. When the principal ray of the light is incident on the lens assembly from an off-axis position, the principal ray transmitted through the lens assembly is inclined relative to the optical axis and is parallel or substantially parallel to each other.

2. The thin film characteristic measuring device according to claim 1, wherein, When the angle between the principal ray of the light ray incident on the lens assembly from the optical axis and the optical axis is 0° to 3.7°, the angle between the principal ray of the light ray transmitted through the lens assembly and the optical axis is 0° to 0.1°.

3. The thin film characteristic measuring device according to claim 1, wherein, The light emitted from the light source has a center wavelength of 800 nm to 900 nm and a bandwidth of 100 nm to 200 nm.

4. The thin film characteristic measuring device according to claim 1, wherein, The light source includes an optical fiber for transmitting light, and The optical fiber has a diameter of 10 μm or less and a numerical aperture (NA) of 0.3 or less.

5. The thin film characteristic measuring device according to claim 1, wherein, The light source includes an optical fiber for transmitting light, and The thin film characteristic measuring device further includes a collimator positioned between the light source and the first reflector, and The numerical aperture NA of the collimator is greater than the numerical aperture NA of the optical fiber.

6. The thin film characteristic measuring device according to claim 5, wherein, The optical fiber has a diameter of 10 μm or less, and The size of the light rays passing through the collimator is between 50 μm and 200 μm, where the size is the diameter.

7. The thin film property measuring device according to claim 1, wherein, The angle between the principal rays of the light incident on the lens assembly is controlled by the first actuator.

8. The thin film characteristic measuring device according to claim 1, wherein, The center of the first reflector is located on the extension line of the optical axis of the lens assembly.

9. The thin film characteristic measuring device according to claim 1, further comprising: A second reflecting mirror reflects the light reflected by the first reflecting mirror; as well as The second actuator causes the second reflector to reciprocate and tilt within a predetermined angle range. The light reflected by the second mirror is incident on the lens assembly.

10. The thin film characteristic measuring device according to claim 9, wherein the thin film characteristic measuring device further comprises: A first transparent plate, through which light irradiated by the light source is transmitted; A third actuator causes the first transparent plate to reciprocate and tilt within a predetermined angle range; The second transparent plate transmits the light that has passed through the first transparent plate through the second transparent plate; as well as A fourth actuator causes the second transparent plate to reciprocate and tilt within a predetermined angle range. Wherein, the tilt axis of the first transparent plate and the tilt axis of the second transparent plate are different from each other, and Light transmitted through the second transparent plate is refracted by the first and second reflectors and then incident on the lens assembly.

11. A thin film characteristic measuring device, the thin film characteristic measuring device being used to measure the thickness or width of a thin film of an object, the thin film characteristic measuring device comprising: The light source is constructed from a superluminescent diode (SLD); A first reflecting mirror reflects light emitted from the light source; The first actuator causes the first reflector to reciprocate and tilt within a predetermined angle range; as well as A lens assembly comprising multiple lenses, wherein light reflected by the first reflecting mirror is incident on and transmitted through the lens assembly. The lens assembly includes: A first lens, wherein the first lens is constructed of a diverging lens; The second lens is disposed behind the first lens and is constructed of a converging lens; A third lens is disposed in front of the first lens and is constructed of a converging lens; A fourth lens, disposed between the third lens and the first lens, and constructed as a converging lens; and A fifth lens, disposed between the third lens and the first lens, and constructed as a diverging lens, and When the principal ray of the light is incident on the lens assembly from an off-axis position, the principal ray transmitted through the lens assembly is inclined relative to the optical axis and is parallel or substantially parallel to each other.

12. The thin film characteristic measuring device according to claim 11, wherein, The lens assembly further includes a sixth lens disposed between the fifth lens and the first lens, and is constructed as a converging lens. The fourth lens is positioned in front of the fifth lens.

13. The thin film characteristic measuring device according to claim 12, wherein, When the angle between the principal ray of the light incident on the lens assembly from the optical axis and the optical axis is 0° to 3.7°, the angle between the principal ray of the light transmitted through the lens assembly and the optical axis is 0° to 0.1°.

14. The thin film characteristic measuring device according to claim 12, wherein, The sum of the focal lengths of the third, fourth, fifth, and sixth lenses, FL1, is shorter than the sum of the focal lengths of the third, fourth, fifth, sixth, and first lenses, FL2. The focal length FL3 of the second lens is longer than that of FL1 and shorter than that of FL2.

15. The thin film characteristic measuring device according to claim 12, wherein, When the diameter of the region formed by light rays parallel to the optical axis of the lens assembly incident on the third lens is D1, The diameter of the region formed when light transmitted through the lens assembly contacts the surface of the object is D2. The sum of the focal lengths of the third lens, the fourth lens, the fifth lens, the sixth lens, and the first lens is FL2, and The focal length of the second lens is FL3. The values ​​of FL3 / FL2 are within ±10% of the values ​​of D2 / D1.

16. The thin film characteristic measuring device according to claim 12, wherein, When the distance between the first reflecting mirror and the third lens is L1, and The distance between the second lens and the object is L2. The L1 and L2 are 20 mm or larger, and The effective focal length of the lens assembly is 85mm.

17. The thin film property measuring device according to claim 12, wherein, The first lens is an asymmetric biconcave lens. The second lens is a plano-convex lens. The third lens is a positive meniscus lens. The fourth lens is an asymmetric biconvex lens. The fifth lens is a plano-concave lens, and The sixth lens is an asymmetric biconvex lens.

18. The thin film characteristic measuring device according to claim 11, wherein, The thin film property measurement device includes: A collimator, positioned between the light source and the first reflector, and The housing, the lens assembly and the first actuator are fixed to the housing, and the housing houses the first reflector and opens toward the collimator.

19. The thin film characteristic measuring device according to claim 18, wherein, Multiple heat dissipation fins are formed in the first actuator.

20. The thin film characteristic measuring device according to claim 11, wherein, The thin film property measuring device also includes: A diffractive optical element, wherein the diffractive optical element is positioned between the light source and the lens assembly.

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