The invention relates to the field of optical switching relays, and in particular to an electromagnetically actuated optical relay that latches by means of liquid surface tension.
Communications systems using optical signals require the use of optical switches and routers. An early approach to optical switching was to convert the optical signal to an electrical signal, use an electrical switch or router and then convert back to an optical signal. More recently, optical relays have been used in which an electrical control signal is used to control the switching or routing of an optical signal. Optical relays typically switch optical signals by using movable solid mirrors or by using the creation of vapor bubbles to alter the index of refraction inside a cavity. The moveable mirrors may use electrostatic latching mechanisms, whereas bubble switches do not latch. Piezoelectric latching relays either use residual charges in the piezoelectric material to latch, or actuate switch contacts containing a latching mechanism.
Liquid metal is also used in electrical relays. A liquid metal droplet can be moved by a variety of techniques, including electrostatic forces, variable geometry due to thermal expansion/contraction, and pressure gradients. When the dimension of interest shrinks, the surface tension of the liquid metal becomes dominant force over other forces, such as body forces (inertia). Consequently, some micro-electromechanical (MEM) systems utilize liquid metal switching.
The present invention relates to an optical switch in which a solid slug is moved within a channel and used to block or unblock an optical path passing through the channel. The solid slug is moved by electromagnets. In an exemplary embodiment, the slug is wetted by a liquid, such as liquid metal, that also adheres to wettable metal contact pads within the channel to provide a latching mechanism. An optical signal may be reflected from the wetted surface of the solid slug and switched to an alternative optical path.
The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however, both as to organization and method of operation, together with objects and advantages thereof, may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail one or more specific embodiments, with the understanding that the present disclosure is to be considered as exemplary of the principles of the invention and not intended to limit the invention to the specific embodiments shown and described. In the description below, like reference numerals are used to describe the same, similar or corresponding parts in the several views of the drawings.
The present invention relates to an electro-magnetically actuated optical relay that switches and latches by means of a wettable magnetic solid slug and a liquid. In a preferred embodiment, the relay uses the magnetic field of an electromagnet to displace a solid magnetic slug. The slug blocks or unblocks an optical path, allowing the switching of optical signals. In the absence of the magnetic field, the solid slug is held in place by surface tension in a liquid, preferably a liquid metal such as mercury, which wets between the solid slug and at least one fixed contact pad on the relay housing.
In one embodiment, micro-machining techniques are used to manufacture the relay. An end view of an optical relay 100 is shown in FIG. 1. In this embodiment, the body of the relay is made up of four layers and is amenable to manufacture by micro-machining. The lowest layer is a circuit substrate 108 that will be described in more detail below with reference to FIG. 3 and FIG. 5. The next layer is a switching layer 106. The switching of the optical signal occurs in a switching channel contained in this layer. The next layer is vent layer 104 that contains a pressure relief vent for relieving pressure variations in the switching channel. The cap layer 102 provides a seal to the top of the switching channel. In operation, an optical signal enters the relay through an optical fiber or waveguide 110 and exits through optical fiber or waveguide 112. Electric coil 114 is one of several that encircle the relay housing and is used to actuate the switching mechanism.
When the solid slug occupies the position shown in
The switch-state may be changed back to the original state shown in
An end view of a further embodiment of an optical relay 100 is shown in FIG. 10. In operation, an optical signal enters the relay through an optical fiber or waveguide 110 and either transmitted in a direct path to exit through optical fiber or waveguide 112 or is reflected and exits through waveguide 202. Electric coil 114 is one of several that encircle the relay housing and is used to actuate the switching mechanism.
While the invention has been described in conjunction with specific embodiments, it is evident that many alternatives, modifications, permutations and variations will become apparent to those of ordinary skill in the art in light of the foregoing description. Accordingly, it is intended that the present invention embrace all such alternatives, modifications and variations as fall within the scope of the appended claims.
This application is related to the following co-pending U.S. patent applications, being identified by the below enumerated identifiers and arranged in alphanumerical order, which have the same ownership as the present application and to that extent are related to the present application and which are hereby incorporated by reference: Application 10010448-1, titled “Piezoelectrically Actuated Liquid Metal Switch”, filed May 2, 2002 and identified by Ser. No. 10/137,691; Application 10010529-1, “Bending Mode Latching Relay”, and having the same filing date as the present application;Application 10010531-1, “High Frequency Bending Mode Latching Relay”, and having the same filing date as the present application;Application 10010570-1, titled “Piezoelectrically Actuated Liquid Metal Switch”, filed May 2, 2002 and identified by Ser. No. 10/142,076;Application 10010571-1, “High-frequency, Liquid Metal, Latching Relay with Face Contact”, and having the same filing date as the present application;Application 10010572-1, “Liquid Metal, Latching Relay with Face Contact”, and having the same filing date as the present application;Application 10010573-1, “Insertion Type Liquid Metal Latching Relay”, and having the same filing date as the present application;Application 10010617-1, “High-frequency, Liquid Metal, Latching Relay Array”, and having the same filing date as the present application;Application 10010618-1, “Insertion Type Liquid Metal Latching Relay Array”, and having the same filing date as the present application;Application 10010634-1, “Liquid Metal Optical Relay”, and having the same filing date as the present application;Application 10010640-1, titled “A Longitudinal Piezoelectric Optical Latching Relay”, filed Oct. 31, 2001 and identified by Ser. No. 09/999,590;Application 10010643-1, “Shear Mode Liquid Metal Switch”, and having the same filing date as the present application;Application 10010644-1, “Bending Mode Liquid Metal Switch”, and having the same filing date as the present application;Application 10010656-1, titled “A Longitudinal Mode Optical Latching Relay”, and having the same filing date as the present application;Application 10010663-1, “Method and Structure for a Pusher-Mode Piezoelectrically Actuated Liquid Metal Switch”, and having the same filing date as the present application;Application 10010664-1, “Method and Structure for a Pusher-Mode Piezoelectrically Actuated Liquid Metal Optical Switch”, and having the same filing date as the present application;Application 10010790-1, titled “Switch and Production Thereof”, filed Dec. 12, 2002 and identified by Ser. No. 10/317,597;Application 10011055-1, “High Frequency Latching Relay with Bending Switch Bar”, and having the same filing date as the present application;Application 10011056-1, “Latching Relay with Switch Bar”, and having the same filing date as the present application;Application 10011064-1, “High Frequency Push-mode Latching Relay”, and having the same filing date as the present application;Application 10011065-1, “Push-mode Latching Relay”, and having the same filing date as the present application;Application 10011121-1, “Closed Loop Piezoelectric Pump”, and having the same filing date as the present application;Application 10011329-1, titled “Solid Slug Longitudinal Piezoelectric Latching Relay”, filed May 2, 2002 and identified by Ser. No. 10/137,692;Application 10011344-1, “Method and Structure for a Slug Pusher-Mode Piezoelectrically Actuated Liquid Metal Switch”, and having the same filing date as the present application;Application 10011345-1, “Method and Structure for a Slug Assisted Longitudinal Piezoelectrically Actuated Liquid Metal Optical Switch”, and having the same filing date as the present application;Application 10011397-1, “Method and Structure for a Slug Assisted Pusher-Mode Piezoelectrically Actuated Liquid Metal Optical Switch”, and having the same filing date as the present application;Application 10011398-1, “Polymeric Liquid Metal Switch”, and having the same filing date as the present application;Application 10011410-1, “Polymeric Liquid Metal Optical Switch”, and having the same filing date as the present application;Application 10011437-1, “Longitudinal Electromagnetic Latching Relay”, and having the same filing date as the present application;Application 10011458-1, “Damped Longitudinal Mode Optical Latching Relay”, and having the same filing date as the present application;Application 10011459-1, “Damped Longitudinal Mode Latching Relay”, and having the same filing date as the present application;Application 10020013-1, titled “Switch and Method for Producing the Same”, filed Dec. 12, 2002 and identified by Ser. No. 10/317,963;Application 10020027-1, titled “Piezoelectric Optical Relay”, filed Mar. 28, 2002 and identified by Ser. No. 10/109,309;Application 10020071-1, titled “Electrically Isolated Liquid Metal Micro-Switches for Integrally Shielded Microcircuits”, filed Oct. 8, 2002 and identified by Ser. No. 10/266,872;Application 10020073-1, titled “Piezoelectric Optical Demultiplexing Switch”, filed Apr. 10, 2002 and identified by Ser. No. 10/119,503;Application 10020162-1, titled “Volume Adjustment Apparatus and Method for Use”, filed Dec. 12, 2002 and identified by Ser. No. 10/317,293;Application 10020241-1, “Method and Apparatus for Maintaining a Liquid Metal Switch in a Ready-to-Switch Condition”, and having the same filing date as the present application;Application 10020242-1, titled “A Longitudinal Mode Solid Slug Optical Latching Relay”, and having the same filing date as the present application;Application 10020473-1, titled “Reflecting Wedge Optical Wavelength Multiplexer/Demultiplexer”, and having the same filing date as the present application;Application 10020540-1, “Method and Structure for a Solid Slug Caterpillar Piezoelectric Relay”, and having the same filing date as the present application;Application 10020541-1, titled “Method and Structure for a Solid Slug Caterpillar Piezoelectric Optical Relay”, and having the same filing date as the present application;Application 10030438-1, “Inserting-finger Liquid Metal Relay”, and having the same filing date as the present application;Application 10030440-1, “Wetting Finger Liquid Metal Latching Relay”, and having the same filing date as the present application;Application 10030521-1, “Pressure Actuated Optical Latching Relay”, and having the same filing date as the present application;Application 10030522-1, “Pressure Actuated Solid Slug Optical Latching Relay”, and having the same filing date as the present application; and Application 10030546-1, “Method and Structure for a Slug Caterpillar Piezoelectric Reflective Optical Relay”, and having the same filing date as the present application.
Number | Name | Date | Kind |
---|---|---|---|
2312672 | Pollard, Jr. | Mar 1943 | A |
2564081 | Schilling | Aug 1951 | A |
3430020 | Von Tomkewitsch et al. | Feb 1969 | A |
3529268 | Rauterberg | Sep 1970 | A |
3600537 | Twyford | Aug 1971 | A |
3639165 | Rairden, III | Feb 1972 | A |
3657647 | Beusman et al. | Apr 1972 | A |
4103135 | Gomez et al. | Jul 1978 | A |
4200779 | Zakurdaev et al. | Apr 1980 | A |
4238748 | Goullin et al. | Dec 1980 | A |
4245886 | Kolodzey et al. | Jan 1981 | A |
4336570 | Brower | Jun 1982 | A |
4419650 | John | Dec 1983 | A |
4434337 | Becker | Feb 1984 | A |
4475033 | Willemsen et al. | Oct 1984 | A |
4505539 | Auracher et al. | Mar 1985 | A |
4582391 | Legrand | Apr 1986 | A |
4628161 | Thackrey | Dec 1986 | A |
4652710 | Karnowsky et al. | Mar 1987 | A |
4657339 | Fick | Apr 1987 | A |
4742263 | Harnden, Jr. et al. | May 1988 | A |
4786130 | Georgiou et al. | Nov 1988 | A |
4797519 | Elenbaas | Jan 1989 | A |
4804932 | Akanuma et al. | Feb 1989 | A |
4988157 | Jackel et al. | Jan 1991 | A |
5278012 | Yamanaka et al. | Jan 1994 | A |
5415026 | Ford | May 1995 | A |
5502781 | Li et al. | Mar 1996 | A |
5644676 | Blomberg et al. | Jul 1997 | A |
5675310 | Wojnarowski et al. | Oct 1997 | A |
5677823 | Smith | Oct 1997 | A |
5751074 | Prior et al. | May 1998 | A |
5751552 | Scanlan et al. | May 1998 | A |
5828799 | Donald | Oct 1998 | A |
5841686 | Chu et al. | Nov 1998 | A |
5849623 | Wojnarowski et al. | Dec 1998 | A |
5874770 | Saia et al. | Feb 1999 | A |
5875531 | Nellissen et al. | Mar 1999 | A |
5886407 | Polese et al. | Mar 1999 | A |
5889325 | Uchida et al. | Mar 1999 | A |
5912606 | Nathanson et al. | Jun 1999 | A |
5915050 | Russell et al. | Jun 1999 | A |
5972737 | Polese et al. | Oct 1999 | A |
5994750 | Yagi | Nov 1999 | A |
6021048 | Smith | Feb 2000 | A |
6180873 | Bitko | Jan 2001 | B1 |
6201682 | Mooij et al. | Mar 2001 | B1 |
6207234 | Jiang | Mar 2001 | B1 |
6212308 | Donald | Apr 2001 | B1 |
6225133 | Yamamichi et al. | May 2001 | B1 |
6278541 | Baker | Aug 2001 | B1 |
6304450 | Dibene, II et al. | Oct 2001 | B1 |
6320994 | Donald et al. | Nov 2001 | B1 |
6323447 | Kondoh | Nov 2001 | B1 |
6351579 | Early et al. | Feb 2002 | B1 |
6356679 | Kapany | Mar 2002 | B1 |
6373356 | Gutierrez | Apr 2002 | B1 |
6389189 | Edwards et al. | May 2002 | B1 |
6396012 | Bloomfield | May 2002 | B1 |
6396371 | Streeter et al. | May 2002 | B2 |
6408112 | Bartels | Jun 2002 | B1 |
6446317 | Figueroa et al. | Sep 2002 | B1 |
6453086 | Tarazona | Sep 2002 | B1 |
6470106 | McClelland et al. | Oct 2002 | B2 |
6487333 | Fouquet | Nov 2002 | B2 |
6501354 | Gutierrez et al. | Dec 2002 | B1 |
6512322 | Wong | Jan 2003 | B1 |
6515404 | Wong | Feb 2003 | B1 |
6516504 | Schaper | Feb 2003 | B2 |
6559420 | Zarev | May 2003 | B1 |
6633212 | Ruan et al. | Oct 2003 | B1 |
6633213 | Dove | Oct 2003 | B1 |
6798937 | Wong | Sep 2004 | B1 |
6803842 | Wong et al. | Oct 2004 | B1 |
6816641 | Wong et al. | Nov 2004 | B2 |
20020037128 | Burger et al. | Mar 2002 | A1 |
20020146197 | Yong | Oct 2002 | A1 |
20020150323 | Nishida et al. | Oct 2002 | A1 |
20020168133 | Saito | Nov 2002 | A1 |
20030012483 | Ticknor et al. | Jan 2003 | A1 |
20030035611 | Shi | Feb 2003 | A1 |
Number | Date | Country |
---|---|---|
0593836 | Oct 1992 | EP |
2418539 | Sep 1979 | FR |
2458138 | Oct 1980 | FR |
2667396 | Sep 1990 | FR |
SHO 36-18575 | Oct 1961 | JP |
SHO 47-21645 | Oct 1972 | JP |
63-276838 | May 1987 | JP |
01-294317 | May 1988 | JP |
08-125487 | May 1996 | JP |
9161640 | Jun 1997 | JP |
WO 9946624 | Sep 1999 | WO |
Number | Date | Country | |
---|---|---|---|
20040202410 A1 | Oct 2004 | US |