Patent Abstract:
A large-aperture direct-view high-speed electro-optic shutter includes an electro-optic polymer material constructed to form a Pockels cell and an integrated photoconducting semiconductor switch. A chromophore-doped polymer material or chromophore copolymer, wherein the chromophore is oriented within the polymer material, exhibits a linear electro-optic effect when an electric field is applied to the device. In one embodiment, the polymer host material comprises one or more of a polycarbonate, amorphous polycarbonate, or polymethylmethacrylate polymer hosts. The optically active chromophore comprising one or more coumarin and coumarin derivatives, stilbene or tolane derivatives is incorporated within the polymer host, forming a guest-host polymer. In another embodiment, the chromophore is chemically bonded to the monomer that forms the polymer, resulting in an optically active copolymer. The electro-optic shutter device is then activated by incident light through the photoconducting semiconductor switch, rendering the Pockels cell to have an optical density of at least 3.0.

Full Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/218,160 filed on Jun. 18, 2009, the complete disclosure of which, in its entirety, is herein incorporated by reference. 
    
    
     GOVERNMENT INTEREST 
     The embodiments herein may be manufactured, used, sold, imported and/or licensed by or for the United States Government without the payment of royalties thereon. 
    
    
     BACKGROUND 
     1. Technical Field 
     The embodiments herein generally relate to electro-optic technology, and, more particularly, to electro-optic shutter devices. 
     2. Description of the Related Art 
     There are various types of conventional optical switches, each of which can be classified as either a passive optical switch or an active optical switch. Typically, a passive optical switch receives incoming light, and changes state based upon the received light. In this regard, some passive optical switches are semiconductors that employ two-photon absorption to activate, while other passive optical switches employ all-optical components and organic dyes. In contrast, active optical switches receive incoming light, and are activated and/or deactivated by a power signal. 
     Optical switches, as described above, are typically employed in telecommunications and fiber optic technologies, and may employ semiconductors or organic polymers. Typically, active optical switches are not employed to propagate images in a whole, un-encoded state, as this can easily be accomplished with a passive device. However, passive devices tend to suffer from several problems. 
     For example, although passive devices are inherently fast, their dynamic range is generally very limited, as there are only so many available molecules to respond. Thus, passive devices can saturate quickly. In addition, the fluence or irradiance threshold to turn a conventional passive device to the “on” state may be intolerably high, effectively preventing the device from performing its intended function. 
     Electro-optic shutters have a quick response time and good attenuation, but conventional active and passive shutters are generally unable to extinguish light evenly over the extent of the electro-optic element. Further, conventional devices are generally passive in nature, in that they use part of the incoming light transient to drive the device to a blocking state. This type of conventional construction has been found to be deficient in speed and effectiveness in blocking optical transients that would be harmful to a human eye or sensor. 
     SUMMARY 
     In view of the foregoing, an embodiment herein provides an electro-optic shutter comprising a first polarizer comprising a first polarizer face, and a second polarizer face positioned opposite the first polarizer face; a Pockels cell comprising a first cell face, a second cell face positioned opposite the first cell face, and an outer circumference disposed therebetween, wherein the first cell face of the Pockels cell is disposed adjacent to the second polarizer face of the first polarizer, and wherein the Pockels cell comprises a polymer material comprising a chromophore-doped copolymer or a guest-host polymer; a photo-conducting semiconductor switch (PCSS) in communication with the Pockels cell; a positive electrode in conductive communication with the PCSS; a negative electrode in conductive communication with the PCSS; and a second polarizer comprising a first face, and a second face positioned opposite the first face, wherein the first face of the second polarizer is disposed adjacent to the second cell face of the Pockels cell. 
     In one embodiment, the polymer material, which may be a poled sheet comprising one or more of a polycarbonate, amorphous polycarbonate, or polymethyl-methacrylate (PMMA) polymer host. In another embodiment, the chromophore-doped copolymer or guest-host polymer comprises one or more of coumarin and coumarin derivatives, or coumaromethacrylate-monomethacrylate copolymer, stilbene or tolane derivatives. Preferably, the chromophore-doped copolymer or guest-host polymer exhibits a linear electro-optic effect upon application of an electric field, the electro-optical activity being greater than approximately 10 pm/V. Furthermore, the chromophore-doped polymer or guest-host polymer preferably exhibits transmission in a visible range of approximately 400 to 700 nm. In another embodiment, the polymer material is optically active. Preferably, the PCSS reacts to light, wherein the light activates the Pockels cell causing it to discharge, and wherein the light-activated Pockels cell has an optical density of at least 3.0. 
     Another embodiment provides a method of manufacturing an electro-optic shutter device, the method comprising providing a transparent conducting electrode material; depositing a polymer sheet comprising a poling axis on the transparent conducting electrode material to form a polymer/electrode coated sheet having two layers of electrode material; heating the polymer/electrode coated sheet to a glass transition temperature of the polymer/electrode coated sheet; and folding the polymer/electrode coated sheet to form a consolidated unit, a Pockels cell having a poling direction, comprising interdigitated three dimensional electrodes to form the electro-optic shutter device. 
     Another embodiment provides a method of manufacturing an electro-optic shutter device, the method comprising providing a transparent conducting electrode material; depositing the transparent conducting electrode material on a poled polymer sheet comprising a poling direction, to form a coated polymer sheet having electrode material on a first side thereof, and a non-electrode side opposite the first side; cutting the coated polymer sheet into a plurality of approximately square pieces; bonding each approximately square piece to an adjacent approximately square piece at the non-electrode side to form a consolidated unit having a poling direction; planing and polishing the consolidated unit to transparency; disposing parallel vertical electrodes in the consolidated unit; depositing a common conductor upon the consolidated unit, a Pockels cell having a poling direction, to conductively connect all vertical electrodes to one another to form an electro-optic polymer Pockels cell; and bonding a photo-conducting semiconductor switch to the electro-optic polymer Pockels cell to form the fast shutter device. 
     Another embodiment provides a large-aperture direct-view high-speed electro-optic shutter includes an electro-optic polymer material forming a Pockels cell and an integrated photoconducting semiconductor switch. A chromophore-doped guest-host polymer material or chromophore-doped copolymer, wherein the chromophore is oriented within the polymer material, exhibits a linear electro-optic effect when an electric field is applied to the device. In one embodiment, the polymer host material comprises one or more of a polycarbonate, amorphous polycarbonate, or polymethylmethacrylate polymer hosts. The optically active chromophore comprising one or more coumarin and coumarin derivatives, stilbene or tolane derivatives is incorporated within the polymer host, forming a guest-host polymer. In another embodiment, the chromophore is chemically bonded to the monomer that forms the polymer, resulting in an optically active copolymer. The electro-optic shutter is then activated by incident light through the photoconducting semiconductor switch, rendering the electro-optic shutter opaque. 
     These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which: 
         FIG. 1  is a partial perspective view of a Pockels cell device according to an embodiment herein; 
         FIGS. 2A-C  are an illustration of preferred chromophore compounds contained within a Pockels cell device according to an embodiment herein; 
         FIG. 3  is a modified index ellipsoid of an electro-optic polymer according to an embodiment herein; 
         FIG. 4  is an exploded perspective view of an electro-optic shutter device according to an embodiment herein; 
         FIG. 5  is a side view illustration of one method of manufacturing an electro-optic shutter according to an embodiment herein; 
         FIG. 6  is a side view illustration of an alternative method of manufacturing an electro-optic shutter according to an embodiment herein; 
         FIG. 7  is a side view illustration of a polishing step and PCSS connecting step involved in manufacturing an electro-optic shutter according to an embodiment herein; 
         FIG. 8  is a side view illustration of a polarizer bonding step involved in manufacturing a completed electro-optic shutter device according to an embodiment herein; 
         FIG. 9A  is a top view of a completed electro-optic shutter device according to an embodiment herein; 
         FIG. 9B  is a cross-sectional view of section A-A of the electro-optic shutter device of  FIG. 9A  according to an embodiment herein; 
         FIG. 10  is a front view of a conformable array comprised of a plurality of electro-optic shutter devices according to an embodiment herein; 
         FIG. 11  is a partial magnified view of the conformable array illustrated in  FIG. 10  according to an embodiment herein; 
         FIG. 12  is a partial view of one quadrant of an assembled array of electro-optic shutter devices according to an embodiment herein; 
         FIG. 13  is a schematic diagram illustrating an example application of an electro-optic shutter device according to an embodiment herein; and 
         FIG. 14  is a circuit diagram of the circuit box of  FIG. 13  according to an embodiment herein. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The embodiments herein, and the various features and advantageous details thereof, are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. 
     The embodiments herein provide an improved high-speed electro-optic shutter having a fast response time and good attenuation, while also being capable of extinguishing light evenly over the extent of the electro-optic element. Furthermore, the embodiments herein provide a Pockels cell based electro-optic shutter device capable of blocking optical transients to such an extent that damage to eyes and sensors does not occur. Referring now to the drawings, and more particularly to  FIGS. 1 through 14 , where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments. 
     The Pockels effect is exhibited in chromophore-doped polymers. Specifically, certain crystals and polymers exhibit a linear electro-optic effect, such that birefringence occurs when the crystal is placed in an electric field. The induced birefringence is proportional to the applied electric field, and is due to the deformation of the indicatrix (index ellipsoid) due to the applied field. When a strong external electric field E is applied, the indicatrix is distorted; the length of the principal axes is modified and the orientation of the indicatrix is also modified as indicated:
 
κ′=κ+ r▪E   (Eq. 1),
 
where r is the Pockels electro-optic tensor.
 
     The indicatrix is renormalized to the new field. The form of a Pockels electro-optic tensor for a guest-host polymer of C ∞ν  symmetry is shown in Equation (2) below. Such a material behaves as a uniaxial crystal. The Pockels electro-optic tensor is a third-rank tensor that is symmetrical in the first two indices, and generally contains 18 independent components. The C ∞ν  symmetry reduces the number of independent components to two, since the non-vanishing components r 13 , r 23 , r 42 , and r 51  are all equal: 
     
       
         
           
             
               
                 
                   
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     Prior attempts at creating large area Pockels-based shutter devices have used plasma electrodes and other contrivances to circumvent the problem of obscuration of the central aperture by the electrode. The requirement of a clear central aperture having low losses is due to the necessity of having lossless intracavity elements for a laser. As a fast shutter not used as a laser intracavity element, the large aperture direct-view Pockels devices face no such restriction. 
     The embodiments herein provide a novel Pockels cell device  100 , and an electro-optic shutter comprising such a Pockels cell device. The Pockels cell device of the embodiments herein comprises a chromophore-doped polymer. The Pockels cell device (i.e., the electro-optic element) operates as a half wave plate when a voltage V π  is applied to the element, and has two opposing transverse surfaces. The chromophore-doped polymer is comprised of a polymer material, which acts as the substrate. In particular, the polymer material (i.e., the substrate) comprises, but is not limited to, one or more of a polycarbonate, amorphous polycarbonate, or polymethylmethacrylate (PMMA) polymer host. Preferably, the polymer is doped with, but is not limited to, one or more of coumarin and coumarin derivatives, stilbene or tolane derivatives in the form of a chromophore-doped guest-host polymer or chromophore-doped copolymer system. 
     In particular, as illustrated in  FIG. 1 , a Pockels cell device  100  is provided, wherein the crystal axes are oriented as shown. The chromophore-doped polymer  101  contains oriented chromophores  102 , which exhibit a linear electro-optic effect (Pockels effect) under the influence of an applied electric field  104 . A new index ellipsoid is formed under the influence of the applied field  104 . The incident polarized light  103  propagates parallel to the x-axis  107 ; the y and z axes of the device  100  are shown as  106  and  105 , respectively. 
     As illustrated in  FIGS. 2A-C , the oriented chromophores are preferably chromophores  210 , being specifically designed to have high electro-optical activity and transmission in the visible region, 400 to 700 nm. In  FIG. 2A , the chromophore  210  is a coumarin derivative  211 , which is attached to the polymer  212 , polymethylmethacrylate (PMMA) resulting in a copolymer. In  FIG. 2B , the chromophore is a stilbene derivative, specifically methoxynitrostilbene  213  and in  FIG. 2C , the chromophore is a tolane derivative, specifically aminonitrotolane  214 . Alternatively, the chromophore may be simply dissolved in the polymer host, resulting in a guest-host system. 
     The incident polarized light  103 , as illustrated in  FIG. 1 , polarized 45° to the z-axis  105 , can be resolved into two s and p polarized components, oriented 45° either side of the z-axis  105  of the poled polymer. One component is advanced by λ/4 and the other component is delayed by λ/4. The result is a total phase difference of λ/2, which rotates the incoming polarization 90° (illustrated as x-axis  107 ). The phase shift Δφ that occurs if light is passed through the poled polymer in the direction of the applied electric field is written as below:
 
Δφ=2π/λ 0   [n   e   −n   o   ]L   (Eq. 3);
 
where Δφ is the phase shift (in radians) of the light of wavelength λ 0  (units of m); n o  is the ordinary refractive index (dimensionless quantity) of the Pockels medium at wavelength λ 0  (units of m); n e  is the extra-ordinary refractive index (dimensionless quantity) at wavelength λ 0  (units of m); r 33  and r 31  are the particular electro-optic constants for the Pockels material (units of m/V); and V is the applied voltage (units of V). The “half wave” voltage V π  follows from the equation below:
 
 V   π   =dλ   0   /L ( r   33   n   e   3   −r   13   n   o   3 )  (Eq. 4).
 
     This voltage is on the order of several hundred volts to several kilovolts in a practical device, and scales in a linear fashion with wavelength. The modified index ellipsoid  200  is illustrated in  FIG. 3 . The z, x and y axes are shown as  202 ,  203 , and  204 , respectively. Under the influence of an applied field  205 , the original index ellipsoid  201  is modified to a new index ellipsoid  206 . The extra-ordinary axis (z-axis  202 ) is changed by ½n e   3 r 33 E ( 208 ) and the ordinary axis (y-axis  204 ) is changed by ½n e   3 r 13 E ( 207 ). The total effective change (from Equation (4)) is the difference r 33 n e   3 −r 13 n o   3 . 
     Examples of EO polymers with high EO coefficients are the Lumera DH series of chromophores based on a dialkoxythiophene type structure. The DH series of chromophores include DH6, DH10, DH13, DH28, all having EO coefficients&gt;40 pm/V in a polycarbonate host. All these chromophore structures are based upon the 2′,2′-dicyanomethylen-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) molecule. Various moieties on the TCF structure are altered to form the DH-series of materials. 
     Most research to date has focused on telecommunications applications requiring low loss and high EO coefficient at 1.3 to 1.5 μm. Some of these near-infrared materials may be suitable for this application when used in films less than 10 μm in thickness. However, the embodiments herein provide chromophore copolymer-doped polymer exhibiting a high transmission rate of from 400 to 700 nm, along with a high EO coefficient in excess of 10 pm/V. 
     The electro-optic shutter device  300  of the embodiments herein, as shown in  FIG. 4 , comprises the above-described Pockels cell device  100 , is comprised of a first polarizer  304  having a first face, and a second face opposite the first face. The Pockels cell device  100  (i.e., the electro-optic element of an electro-optic shutter) has a first face, a second face opposite the first face, and an outer circumference disposed therebetween, the first face of the Pockels cell device  100  is disposed adjacent to the second face of the first polarizer  304 . The Pockels cell device  100  (i.e., the electro-optic element) operates as a half wave plate when a voltage V π  is applied to the element, and has two opposing transverse surfaces. 
     A photo-conducting semiconductor switch (PCSS)  307  is disposed in communication with the Pockels cell device  100 . The PCSS  307  further is in conductive communication with a positive electrode  309  and a negative electrode  308 . Disposed adjacent to the second face of the Pockels cell device  100  is a second polarizer  310  having a first face, and a second face opposite the first face. 
     The first polarizer  304  is disposed adjacent to one transverse surface of the Pockels cell device  100  (i.e., the electro-optic element) and has a first transmission axis oriented 45° relative to the z-axis of the poled polymer. The second polarizer  310  is disposed adjacent to the other transverse surface of the Pockels cell device  100  (i.e., the electro-optic element) and has a second transmission axis 90° different than the first transmission axis. Each electrode  308 ,  309  is disposed on one of the transverse surfaces of the Pockels cell device  100  (i.e., the electro-optic element), and has an electric field which is substantially uniform over the transverse extent of the Pockels cell device  100  (i.e., the electro-optic element). 
     Unpolarized light  301  propagating along axis  302  enters the first polarizer  304  with polarization axis  303 . Vertically polarized light  305 , corresponding with the n e  axis  202 , shown in  FIG. 4 , enters the Pockels cell device  100 . Part of the incident light activates the PCSS  307 . The PCSS  307  causes the negative electrode  308  and the positive electrode  309  to discharge the Pockels cell device  100 . 
     If the intensity of the polarized light  305  is insufficient to trigger the PCSS  307 , the light exits the Pockels cell device  100  as 45° polarized light  313 , and passes through the second polarizer  310  having a polarization axis  311 . However, if the intensity of the light  305  is sufficient to trigger the PCSS  307  to discharge the Pockels cell device  100 , the light exits the Pockels cell device  100  as polarized light  312 , which is 90° from the original polarized light  313  and is blocked by the second polarizer  310  having a polarization axis  311 . This configuration is embodied as a normally on or normally transparent device. 
     An example of a Pockels cell device  100  used in accordance with the embodiments herein may be manufactured as illustrated in  FIG. 5 . In particular, a polymer sheet  401 , comprised of the chromophore-doped copolymer or guest-host polymer  101  of the embodiments herein, having a poling axis  402 , is deposited, in step  403 , on a transparent conducting electrode material  405  and  406 , such as, but not limited to, Indium Tin Oxide (ITO) or Baytron® conductive polymer, as non-limiting examples, so as to form a coated sheet  404 . Specifically, the coated sheet  404  has two layers of electrode material,  405  and  406 , respectively, deposited thereon. 
     Polymer sheet  401  is fabricated by dissolving a chromophore  210  in a suitable polymer  212  such as, but not limited to, PMMA. This mixing process is performed while the polymer  212  is heated above its glass transition temperature (T g ), the temperature at which the polymer becomes soft enough to accommodate the chromophore  210 . The resulting mixture is referred to as a guest-host polymer. The guest-host polymer remains heated above the glass transition temperature to allow forming by rollers, sheet extrusion, or other suitable polymer-melt processing technique to form a sheet of the desired thickness. 
     In the case of copolymers  212 - 214 , such as shown in  FIGS. 2A-C , the copolymers are synthesized according to known techniques and heated above the glass transition temperature to allow forming by rollers, sheet extrusion, or other polymer melt processing technique to form a sheet of the desired thickness. 
     At this point, the polymer sheet  401  may be poled. In other words, the polymer sheet  401  has its constituent chromophore molecules aligned in the proper direction by the application of a high voltage electric field to folded structure  408  during step  407 . The high voltage is applied to the top and bottom surfaces of structure  408  to form a chromophore aligning field in the direction of arrow  409 . Alternatively, in process  419 , shown in  FIG. 6 , the field is applied to structure  420  by applied positive and negative high voltage to alternate electrodes; i.e. even electrodes are negative and odd ones are positive. The resulting chromophore poling field  421  is perpendicular to the spacing of the electrodes. 
     The polymer/electrode coated sheet  404  is then heated to its glass transition temperature, as illustrated in step  407  in  FIG. 5 . The resulting polymer electrode coated sheet  404  is then folded to form a consolidated unit  408 , having interdigitated three dimensional electrodes having a poling direction  409 . 
     Alternatively, as shown in  FIG. 6 , the Pockels cell device  100  of the embodiments herein may be manufactured using process  410 , wherein a poled polymer sheet  411 , having poling direction  412 , has, in step  413 , a transparent conducting electrode material  414 , such as, but not limited to, Indium Tin Oxide (ITO) or Baytron® conductive polymer, as non-limiting examples, deposited thereon, so as to form a coated polymer sheet  415 . This poled polymer sheet  411  is comprised of the chromophore copolymer described herein. The coated polymer sheet  415  has an electrode material  414  on only one side thereof. 
     Then, in step  416 , the coated polymer sheet  415  is cut into a plurality of approximately square pieces  417 . The approximately square pieces  417  are then each bonded to the non-electrode side of the adjacent square piece, as illustrated by step  418 . The approximately square pieces  417  may be bonded to one another using cyanoacrylate cement, as a non-limiting example. However, any suitable conventional means of bonding may be used. Then, in step  419 , all of the approximately square pieces  417  are bonded together to form a consolidated unit  420  having poling direction  421 . 
     Consolidated unit  408 , as illustrated in  FIG. 5 , and consolidated unit  420 , as illustrated in  FIG. 6 , now enter the next step of the manufacturing process  430 , which is the planarization of the poled sheet as illustrated in  FIG. 7 . In particular, consolidated unit  408  and consolidated unit  420  have both surfaces  431  and  432  planed and polished to transparency, as illustrated by step  433 . Through step  433  (i.e., the polishing process), both consolidated unit  408  and consolidated unit  420  end up with the same configuration. Then, in step  434 , the individual parallel vertical electrodes  437  of each individual approximately square piece  417  (shown in  FIG. 6 ) are operatively connected by common conductors  435 . The resulting electro-optic polymer  436  may be poled at this step, if necessary. Then, in step  438 , the PCSS  307  is bonded and connected to the electro-optic polymer  436  to form the Pockels cell device  100  of the embodiments herein. 
     To form the completed electro-optic shutter device  300  of the embodiments herein, as shown in  FIG. 8 , in process  440 , the first polarizer  304  is bonded to the Pockels cell device  100  using an optical adhesive  442 , by coating the optical adhesive  442  on the Pockels cell device  100 , and applying pressure to the first polarizer  304  in the direction shown. Similarly, the second polarizer  310  is bonded to the Pockels cell device  100  using an optical adhesive  444 , by applying optical adhesive  444  to the Pockels cell device, and applying pressure to the second polarizer  310  in the direction shown. The first polarizer  304  and the second polarizer  310  are oriented in a crossed configuration. Finally, in step  445 , curing to remove voids and bubbles is carried out to yield a finished electro-optic shutter device  300 . 
     As illustrated in  FIGS. 9A and 9B , the electro-optic shutter device  300  of the embodiments herein is comprised of the Pockels cell device having the PCSS  307  bonded thereto. The dimensions A and B of the electro-optic shutter are variable, and determined by the application. In one non-limiting example, the dimensions A and B are on the order of 1 cm. Three-dimensional interdigitated electrodes  453  and  454  are connected to a high voltage source by pads  455  and  456 . 
     A cross-sectional view of the electro-optic shutter device  300  through A-A shows the thickness L (from Equation (4)), and is generally approximately millimeters, but may be tailored to the desired application. Likewise, the electrode spacing D is generally approximately, but not limited to, 0.5 to 1.0 mm, and may be tailored to the desired application. Light propagates through the device  300  in the direction shown through second polarizer  310  and first polarizer  304 . 
     As illustrated in  FIG. 10 , in the general process  460 , a completed unit can be assembled in a mosaic-like fashion, by assembling a plurality of electro-optic shutter devices  300  together. In particular, in process  461 , the individual electro-optic shutter devices  300  are bonded to a suitable substrate, adjacent to one another, to form a conformable array  464 . The bonding can be accomplished using a silicone-based adhesive  462  or similar material. Preferably, the adhesive used is sufficiently rigid to support the deposition of electrically conducting strips  463 . The strips  463  carry the electrical charge necessary to operate the individual electro optic elements  300 . The individual electro-optic shutter elements  300  can be joined to form a curved element, if desired. 
     As illustrated in  FIG. 11 , which is an expanded view of the array  464  of joined electro-optic elements cell shown in  FIG. 10 , the electro optic shutter elements  300  are embedded in an insulating adhesive material  462 . The electrically conducting strips  463  in  FIG. 10  are split into  473  and  475  as described in  FIG. 11 . Ground common connector strip  473  carries an electrical charge via a smaller conducting strip  474  to the PCSS  307 . Another parallel strip, a positive common connector  475 , carries an opposite electrical charge to the opposing electrodes of the electro-optic shutter elements  300  via a strip  474  attached to a pad  476 . The connectors  473  and  475  are potted within the insulating adhesive material  462 , so as to protect the user against electrical shock. 
       FIG. 12  shows one quadrant of an assembled array  480  of electro-optic shutter devices  300 . The electro-optic shutter devices  300  are potted in an opaque electrically insulating polymer  487  that stabilizes the electro-optic shutter elements  300  against movement, and prevents unwanted light from passing around the electro-optic shutter elements  300 . Each row of electro-optic shutter elements  300  is connected electrically by a positive common connector  475  and common ground connector  473 . The common connectors  473  and  475  terminate in a positive pad  482  and ground pad  481  that allow electrical connection to the high voltage positive bus  486  and ground bus  485 . The connections to the positive high voltage bus  486  are accomplished by positive conducting strip  484 , and the connections to the ground bus are accomplished by ground conducting strip  483 . These conducting strips can be fabricated using known circuit board fabrication techniques. 
       FIG. 13  illustrates an example application of the electro-optic shutter device of the embodiments herein. In particular, in  FIG. 13 , two completed lens assemblies (i.e., array  480  of electro-optic shutter devices) are attached to an eyeglass frame  491 . Two assemblies (i.e., array  480 ) are used to complete the device  490 . The completed optical device  490  may include opaque side shields or other desired aesthetic features. The positive and ground conducting buses  486  and  485 , as shown in  FIG. 12 , are connected in parallel within the eyeglass frame  491 , terminating in one of the earpieces of the eyeglass frame  491 . 
     An insulated wire pair  493  connects the eyeglass frame  491  to a compact circuit box  492 . The circuit box  492  contains various circuit elements  500 , as shown in  FIG. 14 , and contains an on-off switch  503 , a 9-volt battery connected to a commercially available compact high voltage power supply (not shown) applied to positive terminal  501 . The high voltage applied to terminal  501  passes through a charging resistor  502  and applies the high voltage to the electro-optic shutter elements  300 . 
     The resistor  507  allows the designer to tune the circuit for critically damped operation to maximize the efficacy of the device (i.e., device  490  of  FIG. 13 ). The resistor  508  and inductor  509  are not actual discrete circuit elements, but describe the innate resistance and inductance contained within the electro-optic shutter element  300 . The elements of the PCSS  307  are contained within the electro-optic shutter element  300  as previously described. The elements of the PCSS  307 , when illuminated with light, cause the discharge of the electro-optic shutter element  300  to ground  505 , thus activating the device (i.e., device  490  of  FIG. 13 ) as described above. 
     The Pockels cell device  100  provided by the embodiments herein operates with very fast electrical pulses (sub-nanosecond), and provides a significant advantage in speed over conventional mechanical shutters. Further, the device  100  provides for a higher attenuation than conventional passive chemical dye-based shutters. As discussed above, the Pockels cell device  100  provided by the embodiments herein may be incorporated in a thin, flexible electro-optic shutter device  300  composed entirely of a solid-state polymer. 
     The Pockels cell device  100  provided by the embodiments herein, as well as the electro-optical shutter device  300  comprising same, may be utilized in any application requiring very rapid blocking of an optical transient, including protection from damaging laser pulses from the millisecond regime to the nanosecond regime, and even to block pulses down to the femtosecond regime. In particular, the Pockels cell device  100  and electro-optical shutter device  300  provided by the embodiments herein provide excellent eye and sensor protection. 
     Those skilled in the art will recognize that the Pockels cell device  100 , the electro-optic shutter device  300 , and the method of manufacturing same, as provided by the embodiments herein, have many diverse applications and that the embodiments herein are not limited to the representative examples disclosed herein. Accordingly, the foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.

Technology Classification (CPC): 8