High-precision and high-throughput measurement of optical loss rate in optical devices

Abstract

Several embodiments described herein relate to an optical device metrology system including a light source for emitting light and a non-polarizing beam splitter for splitting the light into a first photodetector optical path and an optical path. A first photodetector is disposed in the first photodetector optical path and measures a total power of the light. An optical device substrate is disposed in the optical path and splits the light into a second photodetector optical path and a third photodetector optical path. A second photodetector is disposed in the second photodetector optical path from the optical device substrate. The second photodetector measures a reflected power of the light. A third photodetector is disposed in the third photodetector optical path. The third photodetector measures a transmitted power of the light. A controller receives a plurality of measurements from the first photodetector, the second photodetector, and the third photodetector to calculate a light loss rate in the optical device substrate.

Description

[Technical Field]

[0001]

[0001] Embodiments of this disclosure relate more broadly to optical devices. In particular, embodiments described herein relate to measurement systems and methods for measuring the percentage light loss of at least one of an optical film, an optical device, or an optical device substrate. [Background technology]

[0002]

[0002] Optical devices, including waveguide combiners such as augmented reality waveguide combiners and flat optical devices such as metasurfaces, are used to assist in image superposition. The generated light propagates through the optical device until the light leaves the optical device and is superimposed on the surrounding environment.

[0003]

[0003] Fabricated optical devices tend to lose light by absorption or scattering as light propagates through the optical device or optical device substrate. Optical devices are fabricated from optical device substrates, and in some cases, optical devices are fabricated from optical films, for example, optical films placed on optical device substrates. It is beneficial to measure the light loss rates from optical films and optical device substrates before, during, and after the manufacture of optical devices.

[0004]

[0004] Therefore, there is a need in the art for a measurement system and method for measuring the optical loss rate of at least one of an optical film, an optical device, or an optical device substrate. [Overview of the project]

[0005]

[0005] In one embodiment, an optical device measurement system is provided. The optical device measurement system includes a light source operable to emit light, a non-polarized beam splitter positioned in the path of light, a first photodetector, a second photodetector, a third photodetector, and a controller. The non-polarized beam splitter is operable to split the light into a first photodetector optical path and an optical light path. The first photodetector is positioned in the first photodetector optical path and is operable to measure the total power of the light. An optical device substrate is positioned in the optical light path and is operable to split the light into a second photodetector optical path and a third photodetector optical path. The second photodetector is positioned in the second photodetector optical path from the optical device substrate. The second photodetector is operable to measure the reflected power of the light. The third photodetector is positioned in the third photodetector optical path. The third photodetector is operable to measure the transmitted power of the light. The controller can be operated to receive multiple measurements from a first photodetector, a second photodetector, and a third photodetector in order to calculate the optical loss rate within the optical device substrate.

[0006]

[0006] In another embodiment, a method is provided using an optical device measurement system. The method involves projecting light from a light source toward an unpolarized beam splitter, splitting the light into a first photodetector optical path and an optical optical path in the unpolarized beam splitter, projecting the light onto a first photodetector in the first photodetector optical path, measuring the total power of the light in the first photodetector optical path in the first photodetector optical path, projecting the light onto an optical device substrate in the optical optical path, splitting the light into a second photodetector optical path and a third photodetector optical path in the optical device substrate, projecting the light onto a second photodetector in the second photodetector optical path, and a second photodetector The device includes measuring the reflected power of light in the optical path of a second photodetector, projecting light onto a third photodetector in the optical path of a third photodetector, measuring the transmitted power of light in the third photodetector's optical path, and the controller collecting a plurality of measurements from the first, second, and third photodetectors, wherein the plurality of measurements include total power, reflected power, and transmitted power, and calculating the optical loss rate in the optical device substrate using the plurality of measurements.

[0007]

[0007] In yet another embodiment, a controller for an optical device measurement system is provided. The controller stores instructions. When an instruction is executed by a computer processor, the controller calculates the optical loss rate of an optical device substrate using a plurality of measurements from a first photodetector, a second photodetector, and a third photodetector. The plurality of measurements are collected by projecting light from a light source toward an unpolarized beam splitter, measuring the total power of the light in a first photodetector in the first photodetector optical path, measuring the reflected power of the light in a second photodetector in the second photodetector optical path, and measuring the transmitted power of the light in a third photodetector in the third photodetector optical path. The unpolarized beam splitter splits the light into a first photodetector optical path and an optical path. The second photodetector optical path is formed by light reflected from an optical device substrate located in the optical path. The third photodetector optical path is formed by light transmitted through an optical device substrate located in the optical path. The plurality of measurements include total power, reflected power, and transmitted power.

[0008]

[0008] To enable a detailed understanding of the features of the present disclosure described above, a more specific description of the present disclosure, which has been briefly summarized above, can be obtained by reference to several embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings are only illustrative embodiments and should not be considered to limit the scope of the present disclosure, and other equally valid embodiments may also be permitted. [Brief explanation of the drawing]

[0009] [Figure 1]

[0009] This is a perspective front view of an optical device substrate according to one of the embodiments described herein. [Figure 2]

[0010] This is a schematic diagram of an optical device measurement system according to one of the embodiments described herein. [Figure 3]

[0011] This is a schematic diagram of a controller according to one of the embodiments described herein. [Figure 4]

[0012] It is a flowchart of a method for determining the optical loss rate according to multiple embodiments described in this specification.

Embodiments for Carrying out the Invention

[0010]

[0013] For ease of understanding, where possible, the same reference numbers have been used to denote the same elements common to the drawings. It is contemplated that the elements and features of one embodiment can be beneficially incorporated into other multiple embodiments without additional description.

[0011]

[0014] Embodiments of the present disclosure generally relate to optical devices. In particular, the embodiments described herein relate to an optical device measurement system for measuring light lost within an optical film, an optical device, and a transparent optical device substrate.

[0012]

[0015] FIG. 1 is a perspective front view of an optical device substrate 101 according to multiple embodiments described in this specification. In some embodiments, the optical device substrate 101 includes a plurality of optical devices 100 disposed on a surface 103 of the optical device substrate 101. The optical device 100 can be a waveguide combiner used in virtual reality, augmented reality, or mixed reality. In some embodiments that can be combined with other multiple embodiments described herein, the optical device 100 is a flat optical device such as a metasurface.

[0013]

[0016] The optical device substrate 101 can be any optical device substrate used in the relevant technical field according to the application of the optical device substrate 101. Further, the optical device substrate 101 can have various shapes, thicknesses, and diameters. For example, the optical device substrate 101 can have a diameter of from about 150 mm to about 300 mm. The optical device substrate 101 can have a circular, rectangular, or square shape. The optical device substrate 101 can have a thickness between about 300 μm and about 1 mm. Although only nine optical devices 100 are illustrated on the optical device substrate 101, any number of optical devices 100 can be arranged on the surface 103. The light loss rates of the optical film, the optical device substrate 101, and the optical device 100 described herein are measured using the optical device measurement system 200 and method 400 described herein.

[0014]

[0017] FIG. 2 is a schematic diagram of the optical device measurement system 200. The optical device measurement system 200 is operable to measure the amount of light (e.g., absorbed) lost by the optical device substrate 101, an optical film disposed on the optical device substrate 101, or the optical device 100. The optical device substrate 101, the optical device 100, or the optical device film of the optical device substrate 101 can be measured at one or more stages of manufacture.

[0015]

[0018] The optical device measurement system 200 includes a light source 202, a fiber coupler 204, a half-wave plate 206, a polarization beam splitter 208, a non-polarization beam splitter 210, a first photodetector 212, a second photodetector 214, and a third photodetector 216. The light source 202, the first photodetector 212, the second photodetector 214, and the third photodetector 216 communicate with a controller 240.

[0016]

[0019] The optical device measurement system 200 is operable to support the optical device substrate 101. The optical device substrate 101 may include at least one optical device 100 disposed on the optical device substrate 101. In some embodiments, the optical device 101 includes an optical film disposed thereon. In some embodiments, the optical device substrate 101 may be disposed on a substrate support 220 (e.g., an edge ring) to support the optical device substrate 101 within the optical device measurement system 200.

[0017]

[0020] The light source 202 is operable to emit light through the fiber coupler 204. In one embodiment, which may be combined with other embodiments described herein, the light source 202 is a light-emitting diode (LED). In another embodiment, the light source is a laser, such as a red / green / blue (RGB) laser. The RGB laser may alternately or simultaneously emit a combination of blue light with a wavelength of about 473 nm, green light with a wavelength of about 520 nm, and red light with a wavelength of about 642 nm.

[0018]

[0021] The light emitted from the light source 202 is split into a first photodetector optical path 230A and an optical optical path 230B in the non-polarized beam splitter 210. The first photodetector optical path 230A is directed to the first photodetector 212. The first photodetector 212 receives the total power (P) of the light emitted from the light source 202. tot It is operable to measure ). The optical path 230B is directed towards the optical device substrate 101.

[0019]

[0022] The light that travels along the optical path 230B is split into a second photodetector optical path 230C and a third photodetector optical path 230D at the optical device substrate 101. The second photodetector optical path 230C is directed towards the second photodetector 214. The second photodetector 214 receives the reflected power (P) of the light emitted from the light source 202. refl The second photodetector 214 is operable to measure the incident angle θ with respect to the optical path 230B. inc It is positioned at θ. In one embodiment, θ incEven if different types of light are emitted from the light source 202, the optical path length inside the optical device substrate 101 is maintained so as not to change. In one embodiment, the incident angle is about 6° ± 0.5°. In a plurality of other embodiments, a plurality of other angles may be used. The third photodetector optical path 230D is directed toward the third photodetector 216. The third photodetector 216 is operable to measure the transmission power (P trans ) of the light emitted from the light source 202.

[0020]

[0023] Using the first photodetector 212 disposed within the first photodetector optical path 230A, the total power P tot is measured, and using the second photodetector 214 disposed within the second photodetector optical path 230C, the reflected power P refl is measured, and using the third photodetector 216 within the third photodetector optical path 230D, the transmission power P trans is measured, whereby measurement values of the power of the projected light at three detection points are obtained. By the total power P tot , the reflected power P refl , and the transmission power P trans along three separate optical paths, the light loss rate can be measured in a completely optical manner. The optical device measurement system 200 obtains measurement values of the three powers without contacting the optical device substrate 101 and does not require mode excitation of the optical device substrate 101, the optical device 100, or the optical film. The measurement without contact or mode excitation improves the accuracy of the measurement of the light loss rate and improves the throughput of the entire manufacturing of the optical device substrate 101, the optical device 100, or the optical film.

[0021]

[0024] Figure 3 shows the controller 240 of the optical device measurement system 200. The optical device measurement system 200 communicates with the controller 240. The controller 240 facilitates the control and automation of the method 400 for measuring the optical loss rate of the optical device substrate 101 as described herein. The controller 240 may include a central processing unit (CPU) 350, memory 360, and support circuit 370. The CPU 350 may be one of any form of computer processor used in an industrial setting to control various processes and hardware (e.g., motors and other hardware) and to monitor processes (e.g., changes in the optical loss rate in the optical device substrate 101 throughout the manufacturing process). The memory 360 is connected to the CPU and may be readily available memory such as random access memory (RAM). Software instructions and data may be coded and stored in the memory 360 to instruct the CPU 350. The support circuit 370 is also connected to the CPU to support the processor. The support circuit 370 may include a cache, power supply, clock circuit, input / output circuit, subsystems, etc. A controller-readable program (or computer instructions) determines which tasks can be executed on the optical device board 101. The program may be controller-readable software and may include, for example, code for monitoring changes in the optical loss rate within the optical device board 101 throughout the manufacturing process, or the wavelength of light emitted by the light source 202.

[0022]

[0025] The controller 240 is configured to facilitate the processes of the optical device measurement system 200. In some embodiments, the controller 240 includes one or more inputs (e.g., three inputs) for a first photodetector 212, a second photodetector 214, and a third photodetector 216, as well as a common ground. The controller 240 is operable to select the wavelength of light emitted from the light source 202. In some embodiments, the controller 240 may emit red, blue, or green light simultaneously. In some embodiments, the controller 240 may emit several combinations of blue, red, or green light simultaneously. In some embodiments, the controller 240 may alternate between red, blue, and green light.

[0023]

[0026] The controller 240 is operable to calculate the optical loss rate of the optical device substrate 101 using multiple measurements from the first photodetector 212, the second photodetector 214, and the third photodetector 216. The multiple measurements are used to calculate the total power P tot Reflection Power P refl , and transmission power P trans This includes the three channels, which provide data with both offsets and fluctuations of the order of 100 nV.

[0024]

[0027] Multiple embodiments of the optical device measurement system 200 described herein provide the ability to remove electrical noise, such as DC offset, to improve the accuracy of optical loss rate measurements. DC offset may result in power drift of the light source or fluctuations in photodetector readings, among other things. Any DC offset in the optical device measurement system 200 can be measured by each of the first photodetector 212, the second photodetector 214, and the third photodetector 216. The controller 240 includes a common ground to remove the DC offset. The controller 240 having a common ground among the first photodetector 212, the second photodetector 214, and the third photodetector 216 allows the controller 240 to determine the level of DC offset in the optical device measurement system 200. The controller 240 ensures that the power measurements obtained from the first photodetector 212, the second photodetector 214, and the third photodetector 216 are not volatile, enabling more accurate and precise measurements of the power obtained at each photodetector.

[0025]

[0028] Figure 4 is a flowchart of method 400 for determining the optical loss rate (e.g., optical loss) using an optical device measurement system 200. A controller 240 is operable to facilitate the steps of method 400. In step 401, light is projected from a light source 202 toward an unpolarized beam splitter 210. In some embodiments, in an optional step 402, the light passes through a fiber coupler 204 to emit light. The fiber coupler 204 couples the light from the light source 202 to allow for a flexible optical system setup.

[0026]

[0029] In an optional step 403, light is projected from the fiber coupler 204 onto the half-wave plate 206. The half-wave plate 206 aligns the polarization of the light emitted from the fiber coupler 204. In an optional step 404, light is projected from the half-wave plate onto the polarizing beam splitter 208. The polarizing beam splitter 208 further fine-tunes the alignment of the light emitted from the fiber coupler 204 and removes unaligned light. In an optional step 405, light is projected from the polarizing beam splitter 208 onto the unpolarizing beam splitter 210.

[0027]

[0030] In step 406, the non-polarized beam splitter 210 splits the light into a first photodetector optical path 230A and an optical optical path 230B. The first photodetector optical path 212 is located within the first photodetector optical path 230A. The first photodetector optical path 230A is formed from the light reflected from the non-polarized beam splitter 210. The optical device substrate 101 is located within the optical optical path 230B. The optical optical path 230B is formed from the light that passes through the non-polarized beam splitter 210 and travels toward the optical device substrate 101.

[0028]

[0031] In step 407, the light reflected from the non-polarized beam splitter 210 is projected toward the first photodetector 212 on the first photodetector optical path 230A. In step 408, the total power P tot However, this is measured by the first photodetector 212. The non-polarized beam splitter 210 has a transmission / reflection splitting ratio. Total power (P tot The ratio is calculated using the splitting ratio of the unpolarized beam splitter 210. The unpolarized beam splitter 210 can split the light from about 20% reflection (80% transmission) to about 80% reflection (20% transmission). In one embodiment, the light projected toward the first photodetector 212 and the light traveling toward the optical device substrate 101 are directed at about 90 degrees relative to each other, but other angles are also considered in this disclosure.

[0029]

[0032] In step 409, light transmitted through the unpolarized beam splitter 210 is projected toward the optical device substrate 101 on the optical path 230B. In some embodiments, the optical device substrate 101 includes an optical film disposed on the optical device substrate 101. In some embodiments, the optical film is a patterned optical film. In some embodiments, the optical device substrate 101 includes one or more optical devices. In step 410, the optical device substrate 101 splits the light into a second photodetector optical path 230C and a third photodetector optical path 230D. When the light interacts with the optical device substrate 101, a portion is absorbed into the optical device substrate 101 (e.g., optical loss rate l), and a portion is reflected (e.g., reflected power P). refl ), a portion is transparent (for example, transparent power P trans The second photodetector 214 is located within the second photodetector optical path 230C. The third photodetector 216 is located within the third photodetector optical path 230D.

[0030]

[0033] In step 411, a portion of the light reflected from the optical device substrate 101 is projected toward the second photodetector 214 on the second photodetector optical path 230C. In step 412, the reflective power P refl However, this is measured by the second photodetector 214. The second photodetector 114 is measured at an incident angle θ with respect to the optical path 230B. inc It is positioned at θ. In one embodiment, θ inc However, even if different types of light are emitted from the light source 202, the optical path length inside the optical device substrate 101 is maintained so as not to change. In one embodiment, the incident angle is approximately 6° ± 0.5°. In some embodiments, several other angles may be used.

[0031]

[0034] In step 413, a portion of the light transmitted through the optical device substrate 101 is projected toward the third photodetector 216 on the third photodetector optical path 230D. In step 414, the transmitted power P trans However, this is measured by the third photodetector 216.

[0032]

[0035] In step 415, the controller 240 collects multiple measurements from the first photodetector 212, the second photodetector 214, and the third photodetector 216. The multiple measurements are used to determine the total power P tot Reflection Power P refl , and transmission power P trans Includes. Total Power P tot Reflection Power P refl , and transmission power P trans These are measured simultaneously by the first photodetector 212, the second photodetector 214, and the third photodetector 216, respectively, to reduce drift or fluctuations within the light source 202. In some embodiments, the optical losses of blue light, green light, and red light can be measured individually.

[0033]

[0036] In step 416, the controller 240 calculates the optical loss rate l in the optical device substrate 101 using multiple measurements. The optical loss rate l (e.g., optical loss) can be measured using formula (1). l = 1 - P refl / P tot -P trans / P tot (1)

[0034]

[0037] In some embodiments, the optical loss rate of the optical device substrate 101 is calculated before the optical device substrate 101 is processed. In other embodiments, the optical loss rate of the optical device substrate 101 is calculated during the processing of the optical device substrate 101. In yet another embodiment, the optical loss rate of the optical device substrate 101 is calculated after the processing of the optical device substrate 101. In yet another embodiment, the optical loss rate of the optical device substrate 101 is calculated before processing, during processing, and after processing, or in some combination thereof.

[0035]

[0038] Method 400 can provide measurements from the first photodetector 212, the second photodetector 214, and the third photodetector 216 within a range of approximately 100 mV, with the three channels on the order of 100 nV (e.g., 10 -6This allows for data with both offset and fluctuation (in terms of accuracy). The fully optical method enables high-throughput measurement of optical loss rates with wavelengths ranging from ultraviolet to infrared. The fully optical method means that the optical device substrate 101 being measured interacts only with the light projected onto it and not with any other physical devices. The design is compatible with multiple substrate chuck designs and enables fully automated measurements.

[0036]

[0039] In summary, an optical device measurement system and method for calculating the optical loss rate of an optical device substrate or optical device are provided herein. The optical device measurement system splits the emitted light into a first photodetector optical path and an optical optical path. The optical device substrate splits the light into a second photodetector optical path and a third photodetector optical path. The first photodetector is located in the first photodetector optical path, the second photodetector is located in the second photodetector optical path, and the third photodetector is located in the third photodetector optical path. By using the photodetectors, measurements of the power of the light projected at three detection points along the three separate optical paths are obtained. The total power P along the three separate optical paths tot Reflection Power P refl , and transmission power P trans This allows for the measurement of optical loss in a completely optical manner. The optical device measurement system acquires three power measurements without contact with the optical device substrate and does not require mode excitation of the optical device substrate, optical device, or optical film. Measurement without contact or mode excitation improves the accuracy of optical loss measurement and increases the overall throughput of manufacturing optical device substrates, optical devices, or optical films. The optical loss is calculated in the controller. The controller receives measurements from the first, second, and third photodetectors. The optical loss can be calculated before, during, or after processing the optical device substrate or optical device, enabling higher throughput. A common ground eliminates the DC offset in the optical device measurement system, and the optical device measurement system operates on the order of 100 nV (e.g., 10 of the optical loss measurement).-6 It enables the measurement of offset and fluctuation (with high accuracy).

Claims

1. A substrate support that can operate to hold a waveguide, A light source capable of emitting light, A non-polarized beam splitter disposed within the light path, the non-polarized beam splitter capable of splitting the light into a first photodetector optical path and an optical optical path, A first photodetector is positioned within the optical path of the first photodetector and is capable of calculating the total power of the light. A second photodetector is positioned within a second photodetector optical path from a waveguide while being held on a substrate support, wherein the waveguide is positioned within an optical optical path and is operable to split the light within the optical optical path into a second photodetector optical path and a third photodetector optical path, and the second photodetector is operable to measure the reflected power of the light. A third photodetector is positioned within the optical path of the third photodetector and is operable to measure the transmitted power of the light, and A controller comprising an input for the first photodetector, an input for the second photodetector, an input for the third photodetector, and a common ground between the first photodetector, the second photodetector, and the third photodetector, wherein the controller is operable to receive a plurality of measurement values ​​from the first photodetector, the second photodetector, and the third photodetector in order to calculate the optical loss rate in the waveguide, and the optical loss rate is calculated as follows: The first photodetector calculates the total power of the light, The second photodetector measures the reflected power of the light, The third photodetector measures the transmission power of the light, and An optical device measurement system comprising a controller, which collects the plurality of measurement values ​​from the first photodetector, the second photodetector, and the third photodetector.

2. The optical device measurement system according to claim 1, wherein the second photodetector is positioned at an incident angle of approximately 5.5° to approximately 6.5° from the optical path.

3. The light source is operable to alternately emit a first light having a first wavelength range, a second light having a second wavelength range, and a third light having a third wavelength range, The optical device measurement system according to claim 1, wherein the controller is operable to receive a plurality of measurements from the first photodetector, the second photodetector, and the third photodetector, and to calculate the optical loss rate in the waveguide for each of the first light, the second light, and the third light.

4. Half-wave plate, and The optical device measurement system according to claim 1, further comprising a polarizing beam splitter, wherein the half-wave plate and the polarizing beam splitter are operable to align the polarization of the light emitted from the light source.

5. Projecting the first light having the first wavelength range from a light source operable to project the first light having the first wavelength range toward a non-polarized beam splitter. In the non-polarized beam splitter, the first light is split into a first photodetector optical path and an optical optical path. Projecting the first light onto the first photodetector in the first photodetector optical path, In the first photodetector, the total power of the first light in the optical path of the first photodetector is calculated. Projecting the first light onto the waveguide in the optical path, In the waveguide, the first light is divided into a second photodetector optical path and a third photodetector optical path. Projecting the first light onto the second photodetector in the second photodetector optical path, In the second photodetector, the reflected power of the first light in the optical path of the second photodetector is measured. Projecting the first light onto the third photodetector in the third photodetector optical path, In the third photodetector, the transmission power of the first light in the optical path of the third photodetector is measured. In the controller, a first plurality of measurements are collected from the first photodetector, the second photodetector, and the third photodetector, wherein the first plurality of measurements include the total power, the reflected power, and the transmitted power. Using the first set of measurements, calculate the first optical loss rate of the first light in the waveguide, and at least, Projecting a second light having a second wavelength range different from the first wavelength range from the light source, and Using a second set of measurements in the second wavelength range obtained from the first and third photodetectors for the second light, the second optical loss rate of the second light in the waveguide is calculated. A method that involves repeating the process.

6. The first light is passed from the light source through the fiber coupler, Projecting the first light from the fiber coupler onto a half-wave plate, Projecting the first light from the half-wave plate to the polarizing beam splitter, and The method according to claim 5, further comprising projecting the first light from the polarizing beam splitter toward the non-polarizing beam splitter.

7. The method according to claim 5, wherein the method is entirely optical.

8. The method according to claim 5, wherein the first optical loss rate of the waveguide can be measured before processing the waveguide, during processing the waveguide, after processing the waveguide, or in combination thereof.

9. The method according to claim 5, wherein the substrate support is operable to support the waveguide.

10. Determining the DC offset level using a common ground between the first photodetector, the second photodetector, and the third photodetector, Using the controller, remove the DC offset of the level. The method according to claim 5, further comprising:

11. A controller for an optical device measurement system, which stores instructions, and when an instruction is executed by a computer processor, the controller, Using a first plurality of measurements from a first photodetector, a second photodetector, and a third photodetector, a first optical loss rate for first light having a first wavelength range in the waveguide of an optical device measurement system is calculated, wherein the first plurality of measurements are: Projecting the first light from a light source operable to project the first light in the first wavelength range toward an unpolarized beam splitter, wherein the unpolarized beam splitter splits the first light into a first photodetector optical path and an optical optical path. In the first photodetector within the first photodetector optical path, the total power of the first light is calculated. Measuring the reflected power of the light in the second photodetector within the second photodetector optical path, wherein the second photodetector optical path is formed by light reflected from the waveguide arranged within the optical path, and measuring the reflected power of the first light, and The third photodetector in the third photodetector optical path measures the transmitted light power, and the third photodetector optical path is formed by the light transmitted through the waveguide arranged in the optical path, and the data is collected by measuring the transmitted light power. The first set of measurements allows for the calculation of the optical loss rate for the first light, including the total power, the reflected power, and the transmitted power, and Using a second set of measurements from the first photodetector, the second photodetector, and the third photodetector, the optical device measurement system calculates a second optical loss rate for a second light having a second wavelength range in the waveguide. Have them do it, The second set of measurements is collected by projecting the second light from the light source, and the second set of measurements includes the total power, reflected power, and transmitted power of the second light having a second wavelength range different from the first wavelength range, in a controller.

12. Calculating the optical loss rate of the waveguide is: Determining the DC offset level using a common ground between the first photodetector, the second photodetector, and the third photodetector; and The DC offset of the aforementioned level is removed using the aforementioned controller. The controller according to claim 11, further comprising:

13. The controller according to claim 11, wherein the controller is operable to select a first wavelength range or a second wavelength range of light emitted from the light source.

14. The controller according to claim 13, wherein the first wavelength range and the second wavelength range include blue light, red light, or green light.

15. The controller according to claim 11, wherein the second photodetector is positioned at an incident angle of about 5.5° to about 6.5° from the optical path.

16. The controller according to claim 11, wherein the first optical loss rate of the waveguide can be measured before processing the waveguide, during processing the waveguide, after processing the waveguide, or in combination thereof.

17. The controller is operable to receive a plurality of measurements from the first photodetector, the second photodetector, and the third photodetector in order to calculate the optical loss rate in the waveguide, and the calculation of the optical loss rate is Using the aforementioned common ground, the DC offset level between the first photodetector, the second photodetector, and the third photodetector is determined, and To remove the DC offset of the level using the controller, The optical device measurement system according to claim 1, which is performed by [the specified method].

18. The optical device measurement system according to claim 3, wherein the controller is operable to select the first light, the second light, or the third light emitted from the light source.

19. Projecting a third light having a third wavelength range different from the first wavelength range and the second wavelength range from the light source, The method according to claim 5, further comprising calculating a third optical loss rate in the waveguide with respect to the third light using a third plurality of measurements from the first photodetector, the second photodetector, and the third photodetector.

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