GB2414549A - A light beam alarm having a control which aligns its transmitter with its receiver - Google Patents
A light beam alarm having a control which aligns its transmitter with its receiver Download PDFInfo
- Publication number
- GB2414549A GB2414549A GB0510733A GB0510733A GB2414549A GB 2414549 A GB2414549 A GB 2414549A GB 0510733 A GB0510733 A GB 0510733A GB 0510733 A GB0510733 A GB 0510733A GB 2414549 A GB2414549 A GB 2414549A
- Authority
- GB
- United Kingdom
- Prior art keywords
- light
- light beam
- alarm
- receiving means
- building
- 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.)
- Granted
Links
- 239000000779 smoke Substances 0.000 claims abstract description 16
- 230000003213 activating effect Effects 0.000 claims description 2
- 230000001419 dependent effect Effects 0.000 claims 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
- G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
- G08B13/181—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems
- G08B13/183—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems by interruption of a radiation beam or barrier
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B17/00—Fire alarms; Alarms responsive to explosion
- G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
- G08B17/103—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
- G08B29/18—Prevention or correction of operating errors
- G08B29/20—Calibration, including self-calibrating arrangements
- G08B29/24—Self-calibration, e.g. compensating for environmental drift or ageing of components
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Optics & Photonics (AREA)
- Fire-Detection Mechanisms (AREA)
Abstract
A light beam alarm 1 such as a smoke or security alarm, comprising: a light transmitter 6 transmitting a beam of light that travels across a predetermined region (e.g. in a part of a building 11); and a light receiver 8 adapted to be aligned with the transmitter to receive the light beam after it has travelled across the predetermined region. The alarm is activated when the receiver's reception signal falls below a predetermined threshold. A motorised adjustment means such as a set of stepping motors and shafts (31, 32, 29, 30, figs. 3-5) may be operated to vary the alignment between the transmitter and receiver in response to a control signal by a control means 34. The motorised adjustment means (31, 32, 29, 30, figs. 3-5) may adjust the position of the transmitter or receiver upwardly or downwardly relative to a horizontal axis (25, fig. 3), or relative to a vertical axis (27, fig. 3) to move them to the left or right. The control signal may be generated automatically when the light transmitter and receiver move out of alignment, or it may be communicated to the control means by a user's handset that may use an infrared or a radio communication signal. A reflector 17 may be mounted across the building to reflect light towards the receiver.
Description
24 1 4549
A LIGHT BEAM ALARM
The present invention relates to a light beam alarm and particularly, but not exclusively to a light beam smoke detector.
It has previously been proposed to provide a light beam smoke detector in a building, the detector comprising a light transmitter on part of the building and a light receiver located elsewhere in the building but aligned with the transmitter so that the receiver receives a light beam transmitted from the transmitter. When so received a non-alarm signal is generated by an alarm circuit connected to the receiver. However if there is a fire in the building, smoke from the fire obscures the light beam so that the signal strength of the light beam received by the receiver is reduced.
When the signal strength falls below a predetermined threshold an alarm signal is generated by the alarm circuit and an alarm, which may be audible, visible, or electronic, is activated.
Such a situation could occur when the smoke detector is first installed in the building and the transmitter and receiver are incorrectly aligned, or could be due to building movement post installation which causes the previously aligned transmitter and receiver to move out of alignment.
Such misalignment could also occur if either a transmitter or receiver housing is moved inadvertently.
According to a first aspect of the invention there is provided a light beam alarm comprising light transmitting means and light receiving means each adapted to be mounted on a building and so aligned that, in use, the light receiving means receives a light beam from the light transmitting means after the light beam has travelled across a predetermined part of the building, means being provided to activate an alarm when the light signal generated by the light beam as received by the receiving means falls below a predetermined threshold, the detector further comprising motorised adjustment means operative to vary the alignment between the light transmitting means and the receiving means in response to a control signal generated by control means.
Preferably the motorised adjustment means is operative to adjust the position of at least one of the light transmitting means and the receiving means about a horizontal axis so as to tilt the transmitting or receiving means upwardly or downwardly relative to the building.
Preferably the motorized adjustment means is operative to adjust the position of at least one of the light transmitting means and the receiving means about a vertical axis so as to move the transmitting or receiving means to the left or right relative to the building.
The adjustment about both horizontal and vertical axes enables at least one of the light transmitting means and the receiving means to be adjusted so as to respectively transmit or receive the light beam within a conical range that extends outwardly from the light transmitting means or the receiving means respectively.
Preferably the motorised adjustment means comprises at least one electric motor.
Preferably the motorised adjustment means comprises two motors, one motor to adjust the position of at least one of the light transmitting means and the light receiving means about the horizontal axis, and one motor to adjust the position of at least one of the light transmitting means and the light receiving means about the vertical axis.
Most preferably the or each motor comprises a DC stepping motor.
Preferably the control signal is generated automatically when the light transmitting means and the light receiving means move out of alignment such that the control means automatically adjusts the position of at least one of the light transmitting means and the light receiving means by activating the motorised adjustment means in response to the control signal generated.
The control signal may be generated manually using a control device at a position remote from the light transmitting means and the light receiving means.
Preferably the control device comprises a user operated handset that communicates with the control means.
Preferably the handset communicates with the control means using an infrared signal.
Alternatively the handset communicates with the control means using a radio signal.
Preferably the light transmitting means and the light receiving means are mounted adjacent one another, the detector further comprising reflective means adapted to be mounted, in use, on a building in spaced relationship to the light transmitting means and the light receiving means so that the light beam is transmitted from the light transmitting means, across the building and onto the reflective means which reflects the light beam back towards the light receiving means so that the light beam is incident on the light receiving means.
Preferably the light transmitting means and the light receiving means are mounted in a single housing.
Alternatively the light transmitting means and the light receiving means are mounted in spaced relationship on a building so that the light beam is transmitted from the light transmitting means, across the building and is incident on the light receiving means.
In this embodiment the light transmitting means and the tight receiving means are mounted in respective separate housings.
Preferably the light source comprises a light emitting diode. Preferably the diode is an infra red diode.
Preferably the light receiving means comprises a diode. Preferably the diode contains a photosensitive cell.
Preferably the reflective means comprises a prism reflector.
In one embodiment the light beam alarm comprises a light beam smoke detector.
In another embodiment the light beam alarm comprises a light beam security alarm.
Other aspects of the present invention may include any combination of the features or limitations referred to herein.
The present invention may be carried into practice in various ways, but embodiments will now be described by way of example only with reference to the accompanying drawings in which: Figure I is a perspective view of a light beam smoke detector in accordance with the present invention; Figure 2 is a side view of a building on which the smoke detector of Figure I is mounted; Figure 3 is a schematic perspective view of part of the smoke detector of Figures I and 2; Figure 4 is a schematic view from the side of the part of the smoke detector of Figure.3; and Figure 5 is a schematic view from below of part of the light beam smoke detector of Figures 3 and 4.
Referring initially to Figure 1 a light beam smoke detector I comprises a cube shaped plastics housing 3, one side of which is formed with two adjacent transparent windows 5, 7. A rear face of the housing 3 is provided with mounting means lo mount the housing 3 on a building.
The mounting means could comprise bolts, brackets or clamps or any other suitable means.
A light transmitter 6 and a light receiver 8 are mounted in the housing 3 behind respective windows 5, 7. The light transmitter 6 comprises an infra red diode which, in use, emits a relatively narrow infra red beam through window 5. Any other suitable light source could alternatively be used to provide a straight, focussed light beam.
The light receiver 8 comprises a receiving diode containing a photo sensitive ceil operative to generate an electric signal when light is incident on the photo sensitive cell. Any suitable light receiver 8 could alternatively be used.
Referring additionally to Figure 2, the housing 3 is mounted on a wall 9 of a building 11 at a height of up to 25 metres so as to be spaced from the floor of the building 1 1. The building 11 may be any building including, for example industrial buildings such as warehouses or factories that are relatively large. The housing 3 is mounted such that the light transmitter 6 and light receiver 8 face away from the wall 9 of the bui Iding 1 1.
The smoke detector I further comprises a second cube shaped, plastics housing 13 that is mounted on a wall 15 of the building 11 that is opposed to wall 9. The distance between the walls 9, 15 can be of the order of 100 meires. The second housing 13 contains reflecting means comprising a prism reflector 17. It will be appreciated that the second housing 13 is mounted on the wall 15 at the same height as the housing 13 so that the prism reflector 17 is horizontally and vertically aligned with, and faces, the light transmitter 6 and the light receiver 8.
The second housing 13 could be mounted higher or lower than the first housing 3 provided that the reflector 17 is aligned with the light transmitter 6 and light receiver 8 in the sense that a light beam from the light transmitting means 6 is reflected off the reflector 17 and onto the light receiver 8.
Referring additionally lo figures 3 to 5, the light transmitter 6 is mounted on a vertical frame 19 that is movably mounted on a horizontal bracket 21 mounted in the housing 3. The part of the bracket 21 that meets the frame 19 comprises a universal pivot point 23. The frame 19, and therefore the light transmitter 6, is movable relative to the bracket 21 about two perpendicular axes 25, 27. Thus, by moving the frame 19, the light transmitter 6 can be directed to the left and right, and up and down, relative to the housing 3 and relative to the window 5.
Two DC electric stepping motors 29, 31 are mounted in the housing 3 behind the frame 19. The output shaft 30 of motor 29 is secured lo the frame 19 at a position horizontally spaced from the pivot point 23. The output shaft.32 of motor.31 is secured to the frame 19 at a position vertically spaced from the pivot point 23. Thus the motor 29 is operative to move the frame 19 and the light transmitter 6 to the left and right by pulling or pushing the frame 19 about a vertical axis, and the motor.31 is operative to move the frame 19 and the light transmitter 6 up or down by pulling or pushing the frame 19 about a horizontal axis.
The motors 29.31 are connected to a power source (not shown) and control means (not shown) operative to control each motor 29, .31 in response to a control signal.
The control means comprises an alarm circuit operative to generate an alarm signal should the signal strength of the light beam received by the light receiver 8 from the light transmitter 6 via the reflector 17 fall below a predetermined threshold. The threshold is set such that an alarm signal is generated when smoke from a fire in the building sufficiently obscures the light beam from the light transmitter 6. The alarm signal can be used by the control means to activate an audible or visual alarm, or to activate any other electronic device as may be required. For example the alarm signal could be used to activate a mobile telecommunications device such as a mobile phone or pager, or to activate a sprinkler system.
The control means also comprises a control circuit operative to measure, in a non fire situation, whether the light beam from the light transmitter 6 is being received by the light receiver 8. If the light beam is not being received, a control signal is generated indicative of this.
Such a signal could include a visual or audible signal that the light beam was not received by the light receiver 8.
In such a situation the control means can do one of two things. Firstly the control means can revert to a manual setting which allows a person to control the motors 29, 31 to adjust the direction of the light beam transmitted from the light transmitter 6. Such adjustment can be achieved via a control device 34 remote from the housing 3 the device 34 being, for example mounted on a wall of the building, or being a portable handset carried by a user. The device.34 could send a signal to the control means to activate the motors 29, 31 via a cable, or via an infrared or radio signal, provided suitable transmitters and receivers are IO provided between the control means and the control device 34. The user can then activate the motors 29, 31 in the housing 3 so that the light beam from the light transmitter 6 is incident on the reflector 17 in the second housing 1.3.
Alternatively the control means can revert to an automatic setting whereby the control means automatically activates the motors 29, .31 so as lo redirect the light beam onto the reflector 17. A sensor circuit can be provided to inform the control means when alignment between the light transmitter 6 and the reflector 17 has been achieved. The sensor circuit operates such that the light beam is sequentially directed to a selection of different positions until a positive signal is generated when the light receiver 8 receives the reflected light beam from the reflector 1 7.
The direction of the light beam from the light transmitter 6 is thus adjusted without any direct user intervention at all, or with user intervention remote from the housing.3 and so there is no need for ladders or lifting apparatus to be used to lift the user up to the housing.3 to make the adjustment manually.
It will be appreciated that the motors 29, 31 could alternatively, or in addition, control the position of the light receiver 8 and/or the reflector 1 7.
Additionally the reflector 17 could be omitted and the light receiver 8 could be mounted in the second housing 13 instead of in the first housing 3. Thus the light beam from the first housing 3 would then be directly incident on the receiver 8 in the second housing 13.
The control means could comprise any suitable electronic or data processing apparatus including software driven microprocessors. The control means could be mounted in either housing 3, 13 or in a stand alone unit in communication with either housing 3, 13.
The control means may include automatic gain control to compensate for light beam degradation as may occur when dirt or dust accumulates on the windows of each housing 3, 13. In addition the sensitivity of the detector I may be adjusted so that the alarm signal is generated for obscuration of the light beam that occurs when a particular threshold of smoke density is reached. Also the alarm signal can be set so as not be generated if the light beam is totally obscured as may occur if an object is inadvertently placed between the transmitter 6 and the reflector.
The above described system could alternatively comprise a light beam security alarm system wherein a beam of light, such as infra red light, is projected from on part of a building to another so as to comprise a light beam security fence. As described above, the alignment between the light transmitting means (6) and the light receiving means (8) can be adjusted to compensate for any relative movement between the light transmitting means (6) and the light receiving means (8) as might be caused by movement of the building during construction, or in use of the building later on.
Claims (24)
1. A light beam alarm comprising light transmitting means and light receiving means each adapted to be mounted on a building and so aligned that, in use, the light receiving means receives a light beam from the light transmitting means after the light beam has travelled across a predetermined part of the building, means being provided to activate an alarm when the light signal generated by the light beam as received by the receiving means falls below a predetermined threshold, the detector further comprising motorised adjustment means operative to vary the alignment between the light transmitting means and the receiving means in response to a control signal generated by control means.
2. The light beam alarm of claim I wherein the motorised adjustment means is operative to adjust the position of at least one of the light transmitting means and the receiving means about a horizontal axis so as to tilt the transmitting or receiving means upwardly or downwardly relative to the building.
3. The light beam alarm of claim I or claim 2 wherein the motorised adjustment means is operative to adjust the position of at least one of the light transmitting means and the receiving means about a vertical axis so as to move the transmitting or receiving means to the left or right relative to the building.
4. The light beam alarm of claim 3 as dependent on claim 2 wherein the adjustment about both horizontal and vertical axes enables at least one of the light transmitting means and the receiving means to be adjusted so as to respectively transmit or receive the light beam within a conical range that extends outwardly from the light transmitting means or the receiving means respectively.
5. The light beam alarm of any one of the preceding claims wherein the motorised adjustment means comprises at least one electric motor.
6. The light beam alarm of any one of claims 3 to 5 as dependent on claim 2 wherein the motorised adjustment means comprises two motors, one motor to adjust the position of at least one of the light transmitting means and the light receiving means about the horizontal axis, and one motor to adjust the position of at least one of the light transmitting means and the light receiving means about the vertical axis.
7. The light beam alarm of claim 5 or claim 6 wherein the or each motor comprises a DC stepping motor.
8. The light beam alarm of any one of the preceding claims wherein the control signal is generated automatically when the light transmitting means and the light receiving means move out of alignment such that the control means automatically adjusts the position of at least one of the light transmitting means and the light receiving means by activating the motorised adjustment means in response to the control signal generated.
9. The light beam alarm of any one of the preceding claims wherein the control signal may be generated manually using a control device at a position remote from the light transmitting means and the light receiving means.
10. The light beam alarm of claim 9 wherein the control device comprises a user operated handset that communicates with the control means.
11. The light beam alarm of claim 10 wherein the handset communicates with the control means using an infrared signal.
12. The light beam alarm of claim 10 wherein the handset communicates with the control means using a radio signal.
13. The light beam alarm of any one of the preceding claims wherein the light transmitting means and the light receiving means are mounted adjacent one another, the alarm further comprising reflective means adapted to be mounted, in use, on a building in spaced relationship to the light transmitting means and the light receiving means so that the light beam is transmitted from the light transmitting means, across the building and onto the reflective means which reflects the light beam back towards the light receiving means so that the light beam is incident on the light receiving means.
14. The light beam alarm of claim 13 wherein the light transmitting means and the light receiving means are mounted in a single housing.
15. The light beam alarm of any one of claims 1 to 12 wherein the light transmitting means and the light receiving means are mounted in spaced relationship on a building so that the light beam is transmitted from the light transmitting means, across the building and is incident on the light receiving means.
16. The light beam alarm of claim 15 wherein the light transmitting 2() means and the light receiving means are mounted in respective separate housings.
17. The light beam alarm of any one of the preceding claims wherein the light source comprises a light emitting diode.
18. The light beam alarm of claim 17 wherein the diode is an infra red diode.
19. The light beam alarm of any one of the preceding claims wherein the light receiving means comprises a diode.
20. The light beam alarm of claim 19 wherein the diode contains a photosensitive cell.
21. The light beam alarm of claim 1.3 or claim 14 wherein the reflective means comprises a prism reflector.
22. The light beam alarm of any one of the preceding claims comprising a light beam smoke detector.
2.3. The light beam alarm of any one of the claims I to 21 comprising a light beam security alarm.
24. A light beam alarm substantially as described herein with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB0411859.2A GB0411859D0 (en) | 2004-05-27 | 2004-05-27 | A light beam smoke detector |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB0510733D0 GB0510733D0 (en) | 2005-06-29 |
| GB2414549A true GB2414549A (en) | 2005-11-30 |
| GB2414549B GB2414549B (en) | 2006-10-11 |
Family
ID=32671168
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB0411859.2A Ceased GB0411859D0 (en) | 2004-05-27 | 2004-05-27 | A light beam smoke detector |
| GB0510733A Active GB2414549B (en) | 2004-05-27 | 2005-05-26 | A light beam alarm |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GBGB0411859.2A Ceased GB0411859D0 (en) | 2004-05-27 | 2004-05-27 | A light beam smoke detector |
Country Status (1)
| Country | Link |
|---|---|
| GB (2) | GB0411859D0 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9746320B2 (en) | 2009-12-29 | 2017-08-29 | Prueftechnik Dieter Busch Ag | Device for adjusting the light source of an electronic alignment device, operation being simplified by motorized adjustment of the light source, and a method in which this device is used |
| EP3258452A1 (en) * | 2016-06-16 | 2017-12-20 | FFE Limited | Beam alignment |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104715561B (en) * | 2013-12-11 | 2017-03-01 | 苏州热工研究院有限公司 | The infrared emission fire detecting system in Spent Fuel Pool room and its installation method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1327231A (en) * | 1970-01-07 | 1973-08-15 | Nat Res Dev | Fire detecting apparatus |
| EP0566352A1 (en) * | 1992-04-11 | 1993-10-20 | Sony Corporation | Optical atmospheric link system |
| JPH07271417A (en) * | 1993-04-05 | 1995-10-20 | Nikki Denso Kk | Positioning control system |
| JPH08223117A (en) * | 1995-02-08 | 1996-08-30 | Sony Corp | Optical space transmission equipment |
| EP0944185A1 (en) * | 1997-10-09 | 1999-09-22 | Seiko Epson Corporation | Space optical transmission apparatus and space optical transmission method |
| US6271758B1 (en) * | 1997-05-29 | 2001-08-07 | Hochiki Corporation | Light projection device for a photoelectric smoke sensor |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3376116B2 (en) * | 1994-08-22 | 2003-02-10 | 関西国際空港株式会社 | Separate type dimmable smoke detector with remote control optical axis adjustment function and fire receiving system using the same |
| JPH09115077A (en) * | 1995-10-13 | 1997-05-02 | Nohmi Bosai Ltd | Photoelectric sensor |
-
2004
- 2004-05-27 GB GBGB0411859.2A patent/GB0411859D0/en not_active Ceased
-
2005
- 2005-05-26 GB GB0510733A patent/GB2414549B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1327231A (en) * | 1970-01-07 | 1973-08-15 | Nat Res Dev | Fire detecting apparatus |
| EP0566352A1 (en) * | 1992-04-11 | 1993-10-20 | Sony Corporation | Optical atmospheric link system |
| JPH07271417A (en) * | 1993-04-05 | 1995-10-20 | Nikki Denso Kk | Positioning control system |
| JPH08223117A (en) * | 1995-02-08 | 1996-08-30 | Sony Corp | Optical space transmission equipment |
| US6271758B1 (en) * | 1997-05-29 | 2001-08-07 | Hochiki Corporation | Light projection device for a photoelectric smoke sensor |
| EP0944185A1 (en) * | 1997-10-09 | 1999-09-22 | Seiko Epson Corporation | Space optical transmission apparatus and space optical transmission method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9746320B2 (en) | 2009-12-29 | 2017-08-29 | Prueftechnik Dieter Busch Ag | Device for adjusting the light source of an electronic alignment device, operation being simplified by motorized adjustment of the light source, and a method in which this device is used |
| EP3258452A1 (en) * | 2016-06-16 | 2017-12-20 | FFE Limited | Beam alignment |
| US10365161B2 (en) | 2016-06-16 | 2019-07-30 | Ffe Limited | Beam alignment |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2414549B (en) | 2006-10-11 |
| GB0510733D0 (en) | 2005-06-29 |
| GB0411859D0 (en) | 2004-06-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| 746 | Register noted 'licences of right' (sect. 46/1977) |
Effective date: 20110223 |
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| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20200526 |
|
| S28 | Restoration of ceased patents (sect. 28/pat. act 1977) |
Free format text: APPLICATION FILED |
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| S28 | Restoration of ceased patents (sect. 28/pat. act 1977) |
Free format text: RESTORATION ALLOWED Effective date: 20210524 |