CN101813797B - Optimal design method of multilayer diffraction optical element - Google Patents
Optimal design method of multilayer diffraction optical element Download PDFInfo
- Publication number
- CN101813797B CN101813797B CN2010101168228A CN201010116822A CN101813797B CN 101813797 B CN101813797 B CN 101813797B CN 2010101168228 A CN2010101168228 A CN 2010101168228A CN 201010116822 A CN201010116822 A CN 201010116822A CN 101813797 B CN101813797 B CN 101813797B
- Authority
- CN
- China
- Prior art keywords
- mrow
- msub
- lambda
- optical element
- multilayer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 132
- 238000000034 method Methods 0.000 title claims abstract description 18
- 239000000463 material Substances 0.000 claims abstract description 17
- 230000010354 integration Effects 0.000 abstract description 9
- 238000003384 imaging method Methods 0.000 abstract description 6
- 238000012938 design process Methods 0.000 description 4
- 239000006185 dispersion Substances 0.000 description 4
- 239000002356 single layer Substances 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 239000010410 layer Substances 0.000 description 3
- 230000004075 alteration Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000193 polymethacrylate Polymers 0.000 description 1
Images
Landscapes
- Diffracting Gratings Or Hologram Optical Elements (AREA)
Abstract
The invention relates to an optimal design method of a multilayer diffraction optical element, which belongs to the technical field of optical design. The optimal design is not realized in the prior art. The method comprises the following steps of: (1) optimally selecting an optical material of the multilayer diffraction optical element according to a surface microstructure height formula of the multilayer diffraction optical element; (2) determining the bandwidth integration average diffraction efficiency distribution by using different design wavelength combinations in the entire working waveband; (3) determining the greatest bandwidth integration average diffraction efficiency and the relative design wavelength in the entire working waveband; and (4) substituting the design wavelength corresponding to the greatest bandwidth integration average diffraction efficiency into the surface microstructure height formula of the multilayer diffraction optical element, and calculating out the optimal surface microstructure height and the optimal design wavelength of the multilayer diffraction optical element. The method is used for designing the multilayer diffraction optical element used for a wide-waveband imaging optical system, and maximizes the bandwidth integration average diffraction efficiency of the multilayer diffraction optical element.
Description
Technical Field
The invention relates to an optimal design method of a multilayer diffraction optical element, which is used for designing the multilayer diffraction optical element of a broadband imaging optical system, can realize the maximization of the bandwidth integral average diffraction efficiency and the quantitative optimal design of the multilayer diffraction optical element, can improve the imaging quality of a refraction/diffraction mixed optical system containing the multilayer diffraction optical element, and belongs to the technical field of optical design.
Background
With the development of optical manufacturing technology, the diffractive optical element creates an independent branch in modern optics, and revolutionizes traditional optical design theory and manufacturing process. The diffractive optical element can be used for correcting various imaging defects such as chromatic aberration, aberration and the like, and brings more design freedom and wide material selectivity to optical design, thereby realizing special optical functions. In the design process of the refraction/diffraction mixed optical system, the diffraction efficiency of the single-layer diffraction optical element is sharply reduced along with the deviation of the central wavelength, so that the imaging quality is influenced. Therefore, the single-layer diffractive optical element can be used only for an optical system of a limited band width. In recent years, multilayer diffractive optical elements have been developed to overcome this disadvantage and achieve an improvement in the diffraction efficiency of a wide band.
At present, the diffraction efficiency of the diffractive optical element of the refraction/diffraction mixed optical system is generally analyzed by adopting a scalar diffraction theory method, and the imaging quality of the refraction/diffraction mixed optical system is pre-evaluated by adopting a method of bandwidth integration average diffraction efficiency and the product of the optical transfer function of the optical system. In the design process of the refraction/diffraction hybrid optical system, two-step design is generally adopted, wherein the first step adopts common optical design software such as zemax, codev and the like to design the optical system, and the second step designs the diffraction efficiency of the diffraction optical element. In the design process of the single-layer diffractive optical element, the design wavelength of the single-layer diffractive optical element is consistent with the central wavelength of the optical system, and then the bandwidth integration average diffraction efficiency is a definite value, but in the design process of the multilayer diffractive optical element, the central wavelength of the multilayer diffractive optical element is the central wavelength of the optical system, and meanwhile, a plurality of groups of design wavelengths exist, so that the bandwidth integration average diffraction efficiencies of the corresponding multilayer diffractive optical elements are different, and the influence on the folding/diffracting mixed optical system is also different.
Regarding the optimal design of the multilayer diffraction optical element, no scientific and reliable design method exists at present. The design wavelength of the multilayer diffraction optical element in the visible light band reported in the prior art is selected to be F light and C light, or the two ends of the band, the height calculation of the surface microstructure of the multilayer diffraction optical element is carried out through the design wavelength and the selected optical material, and whether the bandwidth integral average diffraction efficiency is maximum or not is not considered.
Disclosure of Invention
The invention aims to maximize the bandwidth integral average diffraction efficiency of the multilayer diffraction optical design, and provides an optimal design method of a multilayer diffraction optical element.
Since the structure of the multilayer diffractive optical element has various forms, the multilayer diffractive optical element can be equivalent to a separate type multilayer diffractive optical element regardless of the change of the structural form.
The method of the invention specifically comprises the following steps:
1. optimally selecting optical materials for forming the multilayer diffraction optical element according to a surface microstructure height formula of the multilayer diffraction optical element;
2. in the whole working waveband, different design wavelength combinations are adopted to determine the bandwidth integral average diffraction efficiency distribution;
3. determining the maximum bandwidth integral average diffraction efficiency and the corresponding design wavelength in the whole working waveband;
4. and substituting the determined design wavelength corresponding to the maximum bandwidth integral average diffraction efficiency into a surface microstructure height formula of the multilayer diffraction optical element, and calculating to obtain the optimized surface microstructure height and the optimized diffraction efficiency of the multilayer diffraction optical element.
By utilizing the bandwidth integral average diffraction efficiency of the multilayer diffraction optical element, when the visible light waveband is 0.4-0.7 mu m, polymethacrylate and polycarbonate are used as base materials, and the design wavelengths are 0.4 mu m and 0.7 mu m, the microstructure heights of the harmonic diffraction elements of all layers are 17.372 mu m and 13.476 mu m respectively, so that the obtained bandwidth integral average diffraction efficiency is 95.319%; when the F spectral line and the C spectral line are used as design wavelengths, the heights of the microstructures of the harmonic diffraction elements are 24.171 micrometers and 19.261 micrometers respectively, and the obtained bandwidth integral average diffraction efficiency is 96.832%. The method has the technical effects that the maximum bandwidth integral average diffraction efficiency obtained by the method is 99.253%, the corresponding design wavelength is 0.435 μm and 0.598 μm, the microstructure height of each harmonic diffraction element is 16.460 μm and 12.813 μm respectively, the obtained bandwidth integral average diffraction efficiency is higher than 0.4 μm and 0.7 μm, and the bandwidth integral average diffraction efficiency of 0.435 μm and 0.598 μm are 3.934% and 2.241% respectively when the design wavelength is set, the surface microstructure height of each harmonic diffraction element is small, the optimal design of the multilayer diffraction optical element is realized, the bandwidth integral average diffraction efficiency design of the multilayer diffraction optical element can be realized, and the problem of optimal selection of the design wavelength in the design is solved.
Drawings
Fig. 1 is a schematic structural view of a multilayer diffractive optical element.
FIG. 2 is a graph showing the relationship between diffraction efficiency and wavelength for the designed wavelengths of 0.4 μm and 0.7 μm for the multilayer diffractive optical element.
FIG. 3 is a graph showing the relationship between diffraction efficiency and wavelength for the designed wavelengths of 0.486 μm and 0.656 μm of the multilayer diffractive optical element.
FIG. 4 is a graph showing a relationship between the maximum bandwidth integrated average diffraction efficiency of the multilayer diffractive optical element and the variation of the first design wavelength when the second design wavelength is an arbitrary value from 0.4 μm to 0.7 μm.
FIG. 5 is a graph showing a relationship between the maximum bandwidth integrated average diffraction efficiency of the multilayer diffractive optical element and the variation of the second design wavelength when the first design wavelength is an arbitrary value from 0.4 μm to 0.7 μm.
Fig. 6 is a graph showing a relationship between diffraction efficiency and wavelength when the bandwidth integration efficiency of the multilayer diffractive optical element is maximum.
Fig. 7 is a graph showing the relationship between diffraction efficiency and wavelength for three cases where the design wavelengths of the multilayer diffractive optical element are different, and this graph is also referred to as an abstract drawing.
Detailed Description
The method of the present invention is further described below, and the structure of the multilayer diffractive optical element is shown in FIG. 1, in which the number of layers is two.
The first step is to optimally select optical materials for forming the multilayer diffraction optical element according to a surface microstructure height formula of the multilayer diffraction optical element. According to the expression of the phase delay phi (lambda) of the diffractive optical element in scalar diffraction theory:
φ(λ)＝k[n1(λ)-1]H1+k[n2(λ)-1]H2 (1)
in the formula: λ is the operating wavelength, k is the wavenumber and k is 2 π/λ, n1(lambda) and n2(λ) is a refractive index of the optical material of the multilayer diffractive optical element at a wavelength of λ, H1And H2The heights of the surface microstructures of the layers of the multilayer diffractive optical element are respectively. When the optical material and design wavelength of the multilayer diffraction optical element are lambda1、λ2After determination, the phase delays of the multilayer diffractive optical element form a system of linear equations:
the multilayer diffractive optical element is obtained by solving the system of linear equations (2) with the diffraction order m being 1, and the design wavelength λ of the multilayer diffractive optical element is obtained1、λ2Surface microstructure height H1、H2：
When the design wavelength of the multilayer diffractive optical element is determined and one of the selected materials is a high refractive index, low dispersion optical material and the other is a low refractive index, high dispersion optical material, the denominator in the surface microstructure height formulas (3) and (4) of the multilayer diffractive optical element is the maximum, and then the surface microstructure height of the multilayer diffractive optical element is the minimum.
And secondly, determining the bandwidth integral average diffraction efficiency distribution by adopting different design wavelength combinations in the whole working waveband. When the optical material and the design wavelength of the multilayer diffractive optical element are determined, the height of the surface microstructure of the multilayer diffractive optical element is also determined, and the diffraction efficiency eta of the m-th diffraction order of the multilayer diffractive optical element is determinedm(λ) is:
wherein, <math>
<mrow>
<mi>sin</mi>
<mi>c</mi>
<mrow>
<mo>(</mo>
<mi>x</mi>
<mo>)</mo>
</mrow>
<mo>=</mo>
<mfrac>
<mrow>
<mi>sin</mi>
<mrow>
<mo>(</mo>
<mi>πx</mi>
<mo>)</mo>
</mrow>
</mrow>
<mi>πx</mi>
</mfrac>
</mrow>
</math>
at a design wavelength of λ in the multilayer diffractive optical element1、λ2The bandwidth-integrated average diffraction efficiency eta of the m-th diffraction ordermint(λ1，λ2) Comprises the following steps:
in the formula: lambda [ alpha ]min、λmaxRespectively representing the minimum and maximum wavelengths of the operating band.
And thirdly, determining the maximum bandwidth integral average diffraction efficiency and the corresponding design wavelength in the whole working waveband. After the materials constituting the multilayer diffractive optical element are determined, when the wavelength λ is designed1、λ2In the case of a pair of different variation amounts, it is found from equation (6) that the bandwidth-integrated average diffraction efficiency of the multilayer diffractive optical element also varies. When the design wavelength lambda1Is a fixed wavelength, λ2Is a wavelength from the minimum λminTo a maximum wavelength lambdamaxAny value in between, there is a maximum bandwidth integrated mean diffraction efficiency ηmint(λ1)maxThen, based on the principle, different design wavelengths λ can be drawn1The maximum bandwidth at time integrates the change in diffraction. Similarly, when the design wavelength λ2Is a fixed wavelength, λ1Is a wavelength from the minimum λminTo a maximum wavelength lambdamaxAny value in between, there is a maximum bandwidth integrated mean diffraction efficiency ηmint(λ2)maxThen, according to the principle, different design wavelengths λ are drawn2The maximum bandwidth at time integrates the change in diffraction. According to the definition of the bandwidth integral average diffraction efficiency, the maximum bandwidth integral average diffraction efficiency and the first design wavelength lambda1The maximum bandwidth integral average diffraction efficiency distribution graph, and the maximum bandwidth integral average diffraction efficiency and the second design wavelength lambda2The distribution diagram of the maximum bandwidth integral average diffraction efficiency shows that the design wavelength corresponding to the maximum bandwidth integral average diffraction efficiency of the multilayer diffractive optical element is a pair of symmetrical points, and the bandwidth integral average diffraction efficiency of the multilayer diffractive optical element can be maximized, namely (lambda)1，λ2，ηmmax) And (lambda)2，λ1，ηmmax) The corresponding design wavelength is the bandwidth productThe design wavelength of the multilayer diffractive optical element at which the average diffraction efficiency is maximized is divided.
And fourthly, substituting the determined design wavelength corresponding to the maximum bandwidth integral average diffraction efficiency into a surface microstructure height formula of the multilayer diffraction optical element, and calculating to obtain the optimized surface microstructure height and the optimized diffraction efficiency of the multilayer diffraction optical element. Determining a design wavelength according to the maximum bandwidth integral average diffraction efficiency, substituting the design wavelength into surface microstructure height formulas (3) and (4) of the multilayer diffraction optical element to obtain the surface microstructure height of the multilayer diffraction optical element, substituting the optimized surface microstructure height of the multilayer diffraction optical element into a phase delay expression (1) of the multilayer diffraction optical element, and obtaining the diffraction efficiency of the m diffraction order of the optimized multilayer diffraction optical element according to a diffraction efficiency formula (5) of the m diffraction order of the multilayer diffraction optical element.
The method of the present invention is further illustrated by the example of a multilayer diffractive optical element using the high refractive index, low dispersion optical material N-FK51A and the low refractive index, high dispersion material P-SF67 from Schottky, Germany.
When the design wavelength selection waveband of the multilayer diffractive optical element is 0.4 μm and 0.7 μm at two ends, the height of the surface microstructure of the multilayer diffractive optical element is 8.674 μm and 3.934 μm respectively, the bandwidth integration average diffraction efficiency is 95.524%, and the diffraction efficiency distribution is shown in figure 2. When the design wavelength of the multilayer diffractive optical element is selected from an F (0.4861 μm) line and a C (0.6563 μm) line, the surface microstructure height of the multilayer diffractive optical element is 11.700 μm and 5.606 μm, respectively, the bandwidth integral average diffraction efficiency is 97.032%, and the diffraction efficiency distribution is shown in FIG. 3.
When the multilayer diffractive optical element is designed according to the above maximization of the bandwidth-integrated average diffraction efficiency, the relationship between the bandwidth-integrated average diffraction efficiency of the multilayer diffractive optical element and the first design wavelength is shown in fig. 4, and the relationship between the bandwidth-integrated average diffraction efficiency and the second design wavelength is shown in fig. 5. From fig. 4 and 5, it can be seen that the maximum bandwidth integral average diffraction of the multilayer diffractive optical elementThe design wavelength corresponding to the efficiency is a pair of symmetrical points, and the maximization of the bandwidth integral average diffraction efficiency of the multilayer diffraction optical element is realized, namely when the design wavelength is lambda1＝0.435μm，λ2＝0.598μm，ηmmax99.288% when λ1＝0.598μm，λ2＝0.435μm，ηmmax99.288%, the corresponding design wavelength is the design wavelength of the multilayer diffractive optical element with the maximum bandwidth-integrated average diffraction efficiency.
When the design wavelengths of the multilayer diffractive optical element were 0.435 μm and 0.598 μm, the surface microstructure heights of the multilayer diffractive optical element were 8.186 μm and 3.739 μm, respectively, and the bandwidth-integrated average diffraction efficiency was 99.288%, and the diffraction efficiency distribution is shown in fig. 6.
According to the formula (5), the diffraction efficiencies of different methods are obtained
And the diffraction efficiency at the design wavelength determined according to the method of the present invention
Distribution, as shown in FIG. 7.
Claims (1)
1. An optimal design method of a multilayer diffraction optical element is characterized in that (1) optical materials forming the multilayer diffraction optical element are optimally selected according to a surface microstructure height formula of the multilayer diffraction optical element; (2) in the whole working waveband, different design wavelength combinations are adopted to determine the bandwidth integral average diffraction efficiency distribution; (3) determining the maximum bandwidth integral average diffraction efficiency and the corresponding design wavelength in the whole working waveband; (4) substituting the determined design wavelength corresponding to the maximum bandwidth integral average diffraction efficiency into a surface microstructure height formula of the multilayer diffraction optical element, and calculating to obtain the optimized surface microstructure height and the optimized diffraction efficiency of the multilayer diffraction optical element;
the surface microstructure height formula of the multilayer diffraction optical element is as follows:
in the formula: h1And H2Respectively the height of the surface microstructure of each layer of the multi-layer diffraction optical element, m is the diffraction order, lambda1、λ2For the design wavelength, n, of the multilayer diffractive optical element1(λ1)、n1(λ2)、n2(λ1) And n2(λ2) Refractive indices of optical materials of the multilayer diffractive optical element to design wavelengths, respectively;
the bandwidth-integrated average diffraction efficiency is obtained by the following formula:
in the formula:
integrating the mean diffraction efficiency, λ, for the bandwidth of the m-th diffraction ordermin、λmaxRespectively representing the minimum and maximum wavelengths, η, of the operating bandm(λ) is the diffraction efficiency of the m-th diffraction order, ηmSpecific forms of (λ) are:
wherein,
phi (lambda) is the phase retardation of the diffractive optical element in scalar diffraction theory, and lambda is the operating wavelength.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101168228A CN101813797B (en) | 2010-03-03 | 2010-03-03 | Optimal design method of multilayer diffraction optical element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101168228A CN101813797B (en) | 2010-03-03 | 2010-03-03 | Optimal design method of multilayer diffraction optical element |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101813797A CN101813797A (en) | 2010-08-25 |
| CN101813797B true CN101813797B (en) | 2012-02-22 |
Family
ID=42621099
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010101168228A Expired - Fee Related CN101813797B (en) | 2010-03-03 | 2010-03-03 | Optimal design method of multilayer diffraction optical element |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101813797B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104237992A (en) * | 2014-10-13 | 2014-12-24 | 长春理工大学 | Method for analyzing eccentricity errors of multilayer diffractive optical elements |
| CN110824721B (en) | 2019-09-24 | 2021-11-23 | 杭州驭光光电科技有限公司 | Method for designing diffractive optical element and diffractive optical element |
| CN112188065B (en) * | 2020-09-30 | 2022-02-15 | 维沃移动通信有限公司 | Imaging device and electronic apparatus |
| CN112859328A (en) * | 2021-01-13 | 2021-05-28 | 吉林大学 | Optical flow integrated broadband and high-efficiency multilayer diffraction optical element and preparation method thereof |
| CN113970844A (en) * | 2021-10-30 | 2022-01-25 | 西北工业大学 | Optimization design method of free-form surface substrate multilayer diffraction element |
| CN117075329B (en) * | 2023-07-26 | 2024-04-12 | 泰山学院 | Double-layer diffraction optical element optimization method and system and electronic equipment |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101231357A (en) * | 2007-01-22 | 2008-07-30 | 佳能株式会社 | Laminated diffraction optical element |
-
2010
- 2010-03-03 CN CN2010101168228A patent/CN101813797B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101231357A (en) * | 2007-01-22 | 2008-07-30 | 佳能株式会社 | Laminated diffraction optical element |
Non-Patent Citations (3)
| Title |
|---|
| Dean Faklis and G. Michael Morris.Spectral properties of multiorder diffractive lenses.《Applied Optics》.1995,第34卷(第14期),2462-2468. * |
| 白剑,马韬,沈亦兵等.多层衍射光学元件的特性分析.《红外与激光工程》.2006,第35卷44-47. * |
| 董辉，崔庆丰，裴雪丹等.多层衍射光学元件成像特性的研究.《光子学报》.2009,第38卷(第3期),694-698. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101813797A (en) | 2010-08-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101813797B (en) | Optimal design method of multilayer diffraction optical element | |
| Meng et al. | Detector-only spectrometer based on structurally colored silicon nanowires and a reconstruction algorithm | |
| EP4180846A1 (en) | Large-aperture chromatic aberration correction metalens, metalens system, and optical system | |
| US20070103782A1 (en) | Binary type diffractive optical elements for wide spectral band use | |
| CN103217730B (en) | Narrow-band negative filter plate membrane system with gradually-changing optical thicknesses | |
| CN105891925B (en) | 1064 nanometers of polarization independent wideband high-diffraction efficiency bilayer reflection-type all dielectric gratings | |
| US20220214479A1 (en) | High-efficiency, large-area, topology-optimized metasurfaces | |
| CN109856718B (en) | Low-polarization two-dimensional binary blazed grating | |
| JP6780924B2 (en) | Photovoltaic module including condensing optics with sub-wavelength pattern and satellite solar generator including the module | |
| Mahani et al. | Dual mode operation, highly selective nanohole array-based plasmonic colour filters | |
| WO2016058287A1 (en) | Design method for spectrograph and spectrograph | |
| US8659834B2 (en) | Achromatic gradient index singlet lens | |
| Zhang et al. | Folded digital meta-lenses for on-chip spectrometer | |
| JP2022528797A (en) | Diffractive optics, method of designing efficiency achromatic diffractive structure, and method of manufacturing efficiency achromatic diffractive element | |
| CN102236118B (en) | Blazed grating with planar structure | |
| CN102175319A (en) | Discrete wavelength interval high-resolution microspectrometer based on planar integrated waveguide grating | |
| CN104536141A (en) | Linear chromatic dispersion combined prism beam splitting device | |
| JP2003255116A (en) | Optical element | |
| JP6245620B2 (en) | Light source evaluation device | |
| CN110375856A (en) | Spectrum imaging system and method based on glittering plane reflection gratings double before partial wave | |
| CN210242986U (en) | Spectral imaging system based on wavefront division double-blazed plane reflection grating | |
| CN105404002A (en) | Analysis method of effects on diffraction efficiency of multi-layered diffraction optical elements imposed by air gaps | |
| CN104914509A (en) | Double-grating two-waveband Bragg-concave face diffraction grating wavelength division multiplexer | |
| JP5496258B2 (en) | Laminated diffractive optical element and optical system | |
| Lim et al. | CCD photometry of standard stars at Maidanak astronomical observatory in Uzbekstan: transformations and comparisons |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120222 Termination date: 20130303 |