CN102364770A - Parallel etalon-based laser wavelength precision control method - Google Patents
Parallel etalon-based laser wavelength precision control method Download PDFInfo
- Publication number
- CN102364770A CN102364770A CN2011103174088A CN201110317408A CN102364770A CN 102364770 A CN102364770 A CN 102364770A CN 2011103174088 A CN2011103174088 A CN 2011103174088A CN 201110317408 A CN201110317408 A CN 201110317408A CN 102364770 A CN102364770 A CN 102364770A
- Authority
- CN
- China
- Prior art keywords
- wavelength
- laser
- etalon
- etalons
- optical
- 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.)
- Pending
Links
Images
Landscapes
- Semiconductor Lasers (AREA)
- Lasers (AREA)
Abstract
The invention discloses a parallel etalon-based laser wavelength precision control method and device. The method comprises the following steps of: separating a part of laser output from a laser through a coupler, as monitoring laser, dividing the monitoring laser into two beams of laser with same power, and enabling the two beams of laser to enter two etalons with same value, wherein the central wavelengths of the two etalons are respectively shorter and longer relative to the target wavelength; converting light intensity signals of two beams of light emitted from the two etalons into two paths of electric signals, subtracting the two paths of electric signals to obtain a wavelength error signal; and controlling the laser according to the wavelength error signal feedback, so that the wavelength of laser output by the laser is stable in the target wavelength. The parallel etalon-based laser wavelength precision control method and device provided by the invention have the capabilities of improving the control precision of laser wavelength, reducing wavelength control errors and keeping narrow linewidth and low nose.
Description
Technical field
The present invention relates to optical communication field, particularly relate to a kind of optical maser wavelength precision control method and device based on parallelly connected etalon.
Background technology
In industry and scientific research field, the wavelength control of laser is a key technology.Especially in present field of high-speed optical communications, more need accurate optical maser wavelength control, to improve the transmission performance of communication system.
The purpose of optical maser wavelength control is: make wavelength stabilized laser that laser sends certain fixing optical maser wavelength with reference on.Generally use etalon as the optical maser wavelength reference at present.According to the difference of design principle, it is dissimilar that etalon can be divided into air-gap etalon, solid etalon and distribution reflecting grating etalon etc.The fundamental characteristics of etalon is the light of a transmission/reflection specific wavelength, and this wavelength is called as the centre wavelength of etalon.Utilize this characteristic, can through FEEDBACK CONTROL with wavelength stabilized laser on the centre wavelength of etalon.
Referring to shown in Figure 1, the optical maser wavelength control device that adopts usually at present comprises laser 1, coupler 2, etalon 3, photoelectric detector 4 and processor 5, and the laser of laser 1 output is told sub-fraction, as monitor optical through coupler 2.Monitor optical is gone into photoelectric detector 4 through etalon 3 is laggard.Referring to shown in Figure 2, the maximum point of transmitted light intensity of the corresponding etalon 3 of the centre wavelength of etalon 3.The light intensity signal that photoelectric detector 4 will get into light wherein is converted into the signal of telecommunication, and the signal of telecommunication is sent in the processor 5 and handled.Processor 5 is through the signal of telecommunication FEEDBACK CONTROL laser 1 that light intensity signal is converted into, and makes the wavelength stabilized laser of laser 1 output near the centre wavelength of etalon 3.Usually this purpose has following 2 kinds of methods to realize:
(1) pilot signal is modulated on the Wavelength of Laser of laser 1 output the phase place of pilot signal in the signal of telecommunication of detection photoelectric detector 4 outputs, the Wavelength of Laser of FEEDBACK CONTROL laser 1 output.This method can be accurately with the wavelength stabilized laser of laser 1 output centre wavelength at etalon 3, still, the live width of the laser that the pilot signal of extra introducing will 1 output of broadening laser, and increase frequency and phase noise.
(2) Wavelength of Laser of laser 1 not being exported is stabilized on the centre wavelength of etalon 3; But be stabilized on the edge (rising edge or trailing edge) of etalon 3 centre wavelength both sides; Utilize the Wavelength of Laser of monotonicity stable laser 1 output at edge, referring to shown in Figure 3.If the luminous intensity of photoelectric detector 4 outputs representes then that greater than the luminous intensity of point of safes the wavelength of laser 1 is long partially, processor 5 control lasers 1 wavelength is tuning to the shortwave direction; The luminous intensity of photoelectric detector 4 outputs representes then that less than the luminous intensity of point of safes the wavelength of laser 1 is short partially, and processor 5 control lasers 1 wavelength is tuning to the long wave direction.This method does not need the pilot signal of extra introducing; But can't the Wavelength of Laser of laser 1 output be stabilized on the centre wavelength of etalon 3; And can only be stabilized on the edge of centre wavelength both sides of etalon 3; Therefore have certain error with centre wavelength, and the linear influence of laser power, etalon transmission spectrum of this error Stimulated Light device output can change also.
Summary of the invention
The objective of the invention is in order to overcome the deficiency of above-mentioned background technology; A kind of optical maser wavelength precision control method and device based on parallelly connected etalon is provided; Can improve the control precision of laser wavelength, reduce the error of wavelength control, keep narrow linewidth and low noise.
Optical maser wavelength precision control method based on parallelly connected etalon provided by the invention may further comprise the steps: the laser of A, laser output is told part light as monitor optical through coupler, divides two equal bundle monitor optical of success rate said monitor optical; B, two bundle monitor optical are injected centre wavelength lacks and grow partially equal values partially with respect to target wavelength two etalons respectively; The light intensity signal of C, two-beam that two etalons are penetrated is converted into two path signal, and two path signal is subtracted each other, and obtains wavelength error signal; D, come the FEEDBACK CONTROL laser, the Wavelength of Laser of laser output is stabilized on the target wavelength according to said wavelength error signal.
In technique scheme, may further comprise the steps among the step D: when said wavelength error signal greater than 0 the time, the wavelength of laser is short partially, controls that it is tuning to the long wave direction; When said wavelength error signal less than 0 the time, the wavelength of laser is long partially, controls that it is tuning to the shortwave direction.
In technique scheme, the Free Spectral Range of two etalons described in the step B, insertion loss and the linear homogeneous phase of spectrum are together.
In technique scheme, the Free Spectral Range of said two etalons is equal to the 50GHz or the 100GHz optical channel interval of International Telecommunications Union's regulation.
In technique scheme, said two etalons all adopt air-gap type etalon, crystal type etalon or distributed feed-back type etalon.
Optical maser wavelength accurate control device based on parallelly connected etalon provided by the invention; Comprise laser, coupler and processor; Also comprise beam splitter, two etalons, two photoelectric detectors and a subtracter; The laser of said laser output is told part light as monitor optical through coupler, through beam splitter, divides two equal bundle monitor optical of success rate said monitor optical; Two bundle monitor optical inject respectively centre wavelength with respect to target wavelength short partially with two etalons growing equal values partially, two photoelectric detectors are converted into two path signal with the light intensity signal of the light of two etalons ejaculations respectively; Two path signal is subtracted each other in subtracter, obtains wavelength error signal; Wavelength error signal sent in the processor handle, processor comes the FEEDBACK CONTROL laser according to wavelength error signal, and the Wavelength of Laser of laser output is stabilized on the target wavelength.
In technique scheme, said processor comes the FEEDBACK CONTROL laser according to following two kinds of situation: (1) when said wavelength error signal greater than 0 the time, the wavelength of laser is short partially, the wavelength of processor control laser is tuning to the long wave direction; (2) when said wavelength error signal less than 0 the time, the wavelength of laser is long partially, the wavelength of processor control laser is tuning to the shortwave direction.
In technique scheme, the Free Spectral Range of said two etalons, insertion loss and the linear homogeneous phase of spectrum are together.
In technique scheme, the Free Spectral Range of said two etalons is equal to the 50GHz or the 100GHz optical channel interval of International Telecommunications Union's regulation.
In technique scheme, said two etalons all adopt air-gap type etalon, crystal type etalon or distributed feed-back type etalon.
Compared with prior art, advantage of the present invention is following:
(1) the present invention can critically control laser wavelength, and it stably is on the target wavelength, eliminates wavelength error.
(2) the present invention need not increase pilot signal, does not introduce extra interference and noise, promptly keeps narrow linewidth and low noise.
(3) target wavelength can equal the optical channel centre wavelength of International Telecommunications Union's regulation, also can equal other any wavelength.
(4) the present invention does not increase device cost basically, does not increase the control complexity, and circuit is comparatively simple.
Description of drawings
Fig. 1 is the structural representation of existing optical maser wavelength control device;
Fig. 2 be the prior standard tool transmitted spectrum and centre wavelength concern sketch map;
Fig. 3 for existing with laser export centre wavelength dual-side that the Wavelength of Laser point of safes is set in etalon along the time, the transmitted spectrum sketch map of etalon;
The structural representation of Fig. 4 for installing in the embodiment of the invention;
Fig. 5 is that two bundle monitor optical are passed through the transmitted spectrum of two etalons and the sketch map of target wavelength in the embodiment of the invention;
Fig. 6 subtracts each other the curve chart that obtains for two transmitted spectrums among Fig. 5.
Among the figure: 1-laser, 2-coupler, 3-etalon, 4-photoelectric detector, 5-processor, 6-beam splitter, 7-subtracter.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is made further detailed description.
In order to improve the control precision of laser wavelength, reduce the error of wavelength control, keep narrow linewidth and low noise simultaneously, the embodiment of the invention provides a kind of method and apparatus of controlling laser wavelength based on the precision of parallelly connected etalon.
The optical maser wavelength precision control method based on parallelly connected etalon that the embodiment of the invention provides may further comprise the steps:
The laser of A, laser output is told part light as monitor optical through coupler, divides two equal bundle monitor optical of success rate said monitor optical;
B, two bundle monitor optical are injected centre wavelength lacks and grow partially equal values partially with respect to target wavelength two etalons respectively; The Free Spectral Range of two etalons, insertion loss and the linear homogeneous phase of spectrum are together; Free Spectral Range is equal to the 50GHz or the 100GHz optical channel interval of International Telecommunications Union's regulation; Two etalons all adopt air-gap type etalon, to obtain temperature stability preferably; Also can adopt crystal type etalon or distributed feed-back type etalon, so that the centre wavelength of tuning etalon neatly of the mode through changing temperature;
The light intensity signal of C, two-beam that two etalons are penetrated is converted into two path signal, and two path signal is subtracted each other, and obtains wavelength error signal;
D, come the FEEDBACK CONTROL laser, the Wavelength of Laser of laser output is stabilized on the target wavelength according to wavelength error signal.When wavelength error signal greater than 0 the time, the wavelength of laser is short partially, controls that it is tuning to the long wave direction; When wavelength error signal less than 0 the time, the wavelength of laser is long partially, controls that it is tuning to the shortwave direction.
Referring to shown in Figure 4; Optical maser wavelength accurate control device based on parallelly connected etalon provided by the invention; Comprise laser 1, coupler 2, beam splitter 6, two etalons 3, two photoelectric detectors 4, a subtracter 7 and a processor 5; Two etalons 3 are identical pair of standard tools, so its Free Spectral Range, to insert parameters such as loss and spectrum is linear in full accord.Insert the deflection angle of the compensating plate in two etalons 3 through fine setting, make two etalons 3 centre wavelength with respect to target wavelength short partially respectively with appearance value v together partially.If needs are arranged, can make the Free Spectral Range of two etalons 3 be equal to 50GHz or the 100GHz optical channel interval that International Telecommunications Union stipulates.Consider temperature stability, two etalons 3 are all selected air-gap type etalon for use.
Referring to shown in Figure 4, the laser of laser 1 output is told sub-fraction, as monitor optical through coupler 2; Through beam splitter 6, divide two equal bundles of success rate: monitor optical a and monitor optical b monitor optical; Monitor optical a and monitor optical b inject centre wavelength respectively and respectively the light intensity signal of the light of two etalons, 3 ejaculations are converted into two path signal with respect to target wavelength is short partially with 3, two photoelectric detectors 4 of two etalons of growing equal values partially; Two path signal is subtracted each other in subtracter 7, obtains wavelength error signal; Wavelength error signal sent in the processor 5 handle, processor 5 comes FEEDBACK CONTROL laser 1 according to wavelength error signal, and the Wavelength of Laser of laser 1 output is stabilized on the target wavelength.
(1) when wavelength error signal greater than 0 the time, the wavelength of laser 1 is short partially, the wavelength of processor 5 control lasers 1 is tuning to the long wave direction;
(2) when wavelength error signal less than 0 the time, the wavelength of laser 1 is long partially, the wavelength of processor 5 control lasers 1 is tuning to the shortwave direction.
Monitor optical a and monitor optical b respectively the relation of the transmitted spectrum through two etalons 3 and target wavelength referring to shown in Figure 5; The solid line that indicates a is represented the transmitted spectrum of monitor optical a through etalon 3, and the dotted line that indicates b is represented the transmitted spectrum of monitor optical b through etalon 3.Can see that from Fig. 5 monitor optical a and monitor optical b the spectrum line style through two etalons 3 respectively are in full accord, centre wavelength with respect to target wavelength short partially respectively with appearance value v together partially.
Monitor optical a and monitor optical b respectively the spectrum through two etalons 3 subtract each other the curve that obtains and target wavelength relation referring to shown in Figure 6.Because spectrum can not directly subtract each other, therefore need to use two photoelectric detectors 4 respectively the light intensity signal of the transmitted light of two etalons 3 to be converted into the signal of telecommunication, in subtracter 7, two path signal is subtracted each other.Can see that from Fig. 6 monitor optical a and monitor optical b subtract each other the curve that obtains through the transmitted spectrum of two etalons 3 respectively, can represent the Wavelength of Laser of laser 1 output and the error between the target wavelength.And when the Wavelength of Laser of laser 1 output and the error between the target wavelength were zero, it was zero that the transmitted light intensity of two etalons 3 subtracts each other the value that obtains.
Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, belong within the scope of claim of the present invention and equivalent technologies thereof if of the present invention these are revised with modification, then the present invention also is intended to comprise these changes and modification interior.
The content of not doing in this specification to describe in detail belongs to this area professional and technical personnel's known prior art.
Claims (10)
1. optical maser wavelength precision control method based on parallelly connected etalon is characterized in that may further comprise the steps:
The laser of A, laser output is told part light as monitor optical through coupler, divides two equal bundle monitor optical of success rate said monitor optical;
B, two bundle monitor optical are injected centre wavelength lacks and grow partially equal values partially with respect to target wavelength two etalons respectively;
The light intensity signal of C, two-beam that two etalons are penetrated is converted into two path signal, and two path signal is subtracted each other, and obtains wavelength error signal;
D, come the FEEDBACK CONTROL laser, the Wavelength of Laser of laser output is stabilized on the target wavelength according to said wavelength error signal.
2. the optical maser wavelength precision control method based on parallelly connected etalon as claimed in claim 1 is characterized in that, may further comprise the steps among the step D: when said wavelength error signal greater than 0 the time, the wavelength of laser is short partially, controls that it is tuning to the long wave direction; When said wavelength error signal less than 0 the time, the wavelength of laser is long partially, controls that it is tuning to the shortwave direction.
3. the optical maser wavelength precision control method based on parallelly connected etalon as claimed in claim 1 is characterized in that, the Free Spectral Range of two etalons described in the step B, insertion loss and the linear homogeneous phase of spectrum are together.
4. the optical maser wavelength precision control method based on parallelly connected etalon as claimed in claim 3 is characterized in that: the Free Spectral Range of said two etalons is equal to the 50GHz or the 100GHz optical channel interval of International Telecommunications Union's regulation.
5. like each described optical maser wavelength precision control method based on parallelly connected etalon of claim 1 to 4, it is characterized in that: said two etalons all adopt air-gap type etalon, crystal type etalon or distributed feed-back type etalon.
6. optical maser wavelength accurate control device based on parallelly connected etalon; Comprise laser, coupler and processor; It is characterized in that: also comprise beam splitter, two etalons, two photoelectric detectors and a subtracter; The laser of said laser output is told part light as monitor optical through coupler, through beam splitter, divides two equal bundle monitor optical of success rate said monitor optical; Two bundle monitor optical inject respectively centre wavelength with respect to target wavelength short partially with two etalons growing equal values partially, two photoelectric detectors are converted into two path signal with the light intensity signal of the light of two etalons ejaculations respectively; Two path signal is subtracted each other in subtracter, obtains wavelength error signal; Wavelength error signal sent in the processor handle, processor comes the FEEDBACK CONTROL laser according to wavelength error signal, and the Wavelength of Laser of laser output is stabilized on the target wavelength.
7. the optical maser wavelength accurate control device based on parallelly connected etalon as claimed in claim 6; It is characterized in that; Said processor comes the FEEDBACK CONTROL laser according to following two kinds of situation: (1) when said wavelength error signal greater than 0 the time; The wavelength of laser is short partially, and the wavelength of processor control laser is tuning to the long wave direction; (2) when said wavelength error signal less than 0 the time, the wavelength of laser is long partially, the wavelength of processor control laser is tuning to the shortwave direction.
8. the optical maser wavelength accurate control device based on parallelly connected etalon as claimed in claim 6 is characterized in that: the Free Spectral Range of said two etalons, insertion loss and the linear homogeneous phase of spectrum are together.
9. the optical maser wavelength accurate control device based on parallelly connected etalon as claimed in claim 8 is characterized in that: the Free Spectral Range of said two etalons is equal to the 50GHz or the 100GHz optical channel interval of International Telecommunications Union's regulation.
10. like each described optical maser wavelength accurate control device based on parallelly connected etalon of claim 6 to 9, it is characterized in that: said two etalons all adopt air-gap type etalon, crystal type etalon or distributed feed-back type etalon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103174088A CN102364770A (en) | 2011-10-19 | 2011-10-19 | Parallel etalon-based laser wavelength precision control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103174088A CN102364770A (en) | 2011-10-19 | 2011-10-19 | Parallel etalon-based laser wavelength precision control method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102364770A true CN102364770A (en) | 2012-02-29 |
Family
ID=45691326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011103174088A Pending CN102364770A (en) | 2011-10-19 | 2011-10-19 | Parallel etalon-based laser wavelength precision control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102364770A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104733995A (en) * | 2015-02-04 | 2015-06-24 | 昂纳信息技术（深圳）有限公司 | Wave length locking device |
| CN105186282A (en) * | 2015-08-25 | 2015-12-23 | 中国科学院半导体研究所 | High-frequency-stabilization tunable narrow linewidth laser and use method thereof |
| CN117239530A (en) * | 2023-11-10 | 2023-12-15 | 中国科学院精密测量科学与技术创新研究院 | Device and method for automatically searching and locking digital laser frequency |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5798859A (en) * | 1995-07-27 | 1998-08-25 | Jds Fitel Inc. | Method and device for wavelength locking |
| CN1300123A (en) * | 1999-12-16 | 2001-06-20 | 朗迅科技公司 | Method and apparatus for stabilizing wave lenth of laser |
| CN1370344A (en) * | 1999-08-13 | 2002-09-18 | 加利福尼亚技术学院 | In fiber frequency locker |
| CN1435018A (en) * | 1999-12-17 | 2003-08-06 | 康宁O.T.I股份公司 | Method and device for locking the wavelength of optical signal |
| CN1469993A (en) * | 2000-09-19 | 2004-01-21 | 拉姆达控制公司 | Wavelength detector and method of detecting wavelength of an optical signal |
-
2011
- 2011-10-19 CN CN2011103174088A patent/CN102364770A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5798859A (en) * | 1995-07-27 | 1998-08-25 | Jds Fitel Inc. | Method and device for wavelength locking |
| CN1370344A (en) * | 1999-08-13 | 2002-09-18 | 加利福尼亚技术学院 | In fiber frequency locker |
| CN1300123A (en) * | 1999-12-16 | 2001-06-20 | 朗迅科技公司 | Method and apparatus for stabilizing wave lenth of laser |
| CN1435018A (en) * | 1999-12-17 | 2003-08-06 | 康宁O.T.I股份公司 | Method and device for locking the wavelength of optical signal |
| CN1469993A (en) * | 2000-09-19 | 2004-01-21 | 拉姆达控制公司 | Wavelength detector and method of detecting wavelength of an optical signal |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104733995A (en) * | 2015-02-04 | 2015-06-24 | 昂纳信息技术（深圳）有限公司 | Wave length locking device |
| CN105186282A (en) * | 2015-08-25 | 2015-12-23 | 中国科学院半导体研究所 | High-frequency-stabilization tunable narrow linewidth laser and use method thereof |
| CN117239530A (en) * | 2023-11-10 | 2023-12-15 | 中国科学院精密测量科学与技术创新研究院 | Device and method for automatically searching and locking digital laser frequency |
| CN117239530B (en) * | 2023-11-10 | 2024-02-09 | 中国科学院精密测量科学与技术创新研究院 | Device and method for automatically searching and locking digital laser frequency |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100342431B1 (en) | A multi-wavelength locking method and locker for WDM system | |
| US20170019173A1 (en) | Apparatus and method for monitoring optical performance parameter, and optical transmission system | |
| CN102751656B (en) | System and method for monitoring side-mode suppression ratio and channel stability of tunable laser | |
| CN104040924B (en) | There is the shared wavelength locker of periodic transfer filter in network communication path | |
| US20080285977A1 (en) | Method and apparatus for transmitting optical signals | |
| US10103809B2 (en) | Wavelength tunable light source, and optical transceiver using the same | |
| CN104538841A (en) | Hybrid integrated external cavity adjustable laser based on arrayed waveguide grating | |
| CN101888269B (en) | Method for stabilizing wavelength of optical transmitter in WDM-TDMA (Wavelength Division Multiplex-Time Division Multiple Address) mixed PON (Passive Optical Network) system in burst mode | |
| CN103457155A (en) | Hybrid integrated composite cavity wave length-tunable laser transmitter | |
| CN106299992B (en) | Fiber amplifier gain control method and device | |
| CN104330940A (en) | Device for generating Nyquist optical pulse based on ultra-broadband optical frequency comb | |
| CN113671532B (en) | Self-adaptive multichannel wind lidar system | |
| CN109149358A (en) | Tunable narrow-linewidth external cavity semiconductor laser | |
| CN107409000A (en) | A kind of coherent source offset estimation and the coherent receiver of compensation, method and system | |
| CN102364770A (en) | Parallel etalon-based laser wavelength precision control method | |
| CN104253655A (en) | Adjustable-wavelength emitter for TWDM-PON and light network path unit | |
| CN102593697A (en) | Rapid wavelength tunable light source based on self-injection Fabry-Perot laser | |
| CN110460382A (en) | Broadband is adjustable and low phase noise microwave signal generation device | |
| KR101056783B1 (en) | Phased array antenna system using multi-mode dispersion compensating fiber | |
| US12052052B2 (en) | Optical demultiplexer and communication device | |
| KR101748876B1 (en) | Stable milimeter wave source for broadband wireless signal transmission using optical fibre | |
| CN108476069B (en) | Optical transceiver, wavelength control system and method | |
| CN110416861B (en) | Microwave source and control method thereof | |
| EP3333988A1 (en) | Wavelength locking structure of tunable laser and wavelength locking method of tunable laser | |
| US10205520B2 (en) | Method and device for measuring optical signal-to-noise ratio |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20120229 |