CN204129396U - A kind of infra-red liquid crystal phased array chip - Google Patents

Abstract

The utility model discloses an infrared liquid crystal phased array chip. The chip includes an array of electronically controlled liquid crystal phase modulation microcolumns; it includes a liquid crystal material layer, a liquid crystal initial alignment layer, an electrical isolation layer, a patterned electrode layer, a substrate and an infrared anti-reflection film arranged on the upper surface of the liquid crystal material layer in sequence, and The liquid crystal initial alignment layer, electrical isolation layer, common electrode layer, substrate and infrared anti-reflection film are sequentially arranged on the lower surface of the liquid crystal material layer; the patterned electrode layer is composed of sub-electrodes distributed in an array, and each sub-electrode is composed of a square or a rectangular It is composed of conductive film; the electronically controlled liquid crystal phase modulation microcolumn array is divided into array distribution of electronically controlled liquid crystal phase modulation microcolumns, which correspond to the sub-electrodes one by one, and the area of a single sub-electrode is the same as the corresponding The ratio of the light receiving area is 50% to 95%. The chip can realize the functions of beam expansion, beam shrinkage, beam divergence, beam focusing, beam steering and beam scanning, etc., and is easy to couple with other infrared optical optoelectronic mechanical structures, and has good light field adaptability.

Description

An infrared liquid crystal phased array chip

technical field

The utility model belongs to the technical field of infrared beam precision measurement and control, and more specifically relates to an infrared liquid crystal phased array chip. the

Background technique

So far, based on the electromagnetic wave phase modulation technology, the radio frequency phased array technology that realizes the arbitrary shape construction of the electromagnetic beam, adjustable direction projection, electronically controlled space scanning, specific orientation or airspace beam condensation, etc., has shown strong performance in the radar field. It has become a research and development hotspot in infrared beam engineering to find a method for electromagnetic beam phase modulation suitable for infrared bands, and to realize beam building, beam projection, and beam space scanning functions similar to radio frequency electromagnetic waves. With the continuous and rapid development of infrared beam technology and the continuous expansion of application fields, the development can effectively build a special form of focused infrared beam, flexibly realize beam expansion, shrinkage, spread or focus operations, and condense the infrared beam to a specific orientation Infrared phased array technology that can flexibly adjust the beam pointing according to the environment, targets and needs, realize electronically controlled beam space scanning based on prior knowledge or target conditions, and enhance the coupling and matching efficiency with other infrared optical optoelectronic mechanical devices , has received extensive attention and attention. the

At present, the infrared beam construction, shaping and projection technologies that have been widely used are mostly based on conventional refractive or diffractive lens architectures with fixed contours. The swing way is done. The main technical defects are manifested in the following aspects: (1) The volume, mass and inertia of the optical and auxiliary actuators are large, the function is relatively single, and a relatively complicated drive and control device needs to be configured, the response is slow, and the state transition time is long. Continuity makes it difficult to construct, switch or jump the beam state arbitrarily; (2) The infrared optical components used such as typical prisms, lenses, reflectors and astigmatism mirrors, as well as the various optical films produced such as typical Reflective, anti-reflection, and semi-reflective and semi-transparent films, etc., all have a relatively narrow spectral application range, and there are chromatic aberrations or aberrations that are difficult to completely offset with changes in infrared spectrum components. Beam space scanning is often realized based on the reciprocating mechanical translation between the pendulum mirror or the microlens array. There is a single scanning mode constrained by special rotation or translation, limited performance indicators, large mechanical inertia, and relatively complex auxiliary drives. Control device, slow state change, beam scanning operation can only be carried out in accordance with the set order, can not achieve any form of beam scanning, regional cohesion and scanning are difficult to coexist or fast switching and other defects. the

In recent years, based on low-power arrayed electronically controlled liquid crystal micro-optical structures, significant progress has been made in the construction, shaping, swinging and projection of infrared beams with specific shapes. The main functions realized so far include: (1) array The electronically controlled excitation and modulation of the refractive index of the liquid crystal microstructure can be carried out by applying a low-power electrical drive control signal. The steady-state switching time constant of the refractive index has been as low as sub-milliseconds, and the laboratory level has been as low as microseconds. (2) It can realize the electronically controlled switching between beam convergence and diverging modes, and can effectively perform electronically controlled focusing, focusing and focus swing operations, as well as electronically controlled adjustment of beam divergence; (4) The phase modulation and shaping transformation of the beam can be expanded, solidified or modulated according to the set electronic control sequence, so as to have a priori knowledge, beam (5) An ultra-thin liquid crystal structure with a flat end face and a thickness of a micron-scale liquid crystal material, which can be flexibly inserted into the optical path or coupled or even integrated with other optical opto-mechanical structures; (6) ) has the characteristics of maintaining or changing the beam shape by adjusting electrical parameters, effectively adapting to changes in beam spectrum, fluctuations in device power supply, changes in environmental factors, and changes in target characteristics. At present, how to construct an infrared phased array similar to a radio frequency phased array based on the electronically controlled conversion effect of a small and miniaturized electronically controlled liquid crystal structure on the infrared beam has become a difficult problem to be solved for the continued development of infrared beam precision measurement and control technology. and bottleneck problems, new breakthroughs are urgently needed. the

Utility model content

Aiming at the above defects or improvement needs of the prior art, the utility model provides an infrared liquid crystal phased array chip, which can flexibly construct an infrared beam shape, and effectively realize electronically controlled beam expansion, beam shrinkage, beam divergence, beam focusing, and beam adjustment. Direction and beam scanning and other functions, easy to couple with other infrared optical optoelectronic mechanical structures, good light field adaptability. the

In order to achieve the above object, the utility model provides an infrared liquid crystal phased array chip, which is characterized in that it includes an electronically controlled liquid crystal phase modulation microcolumn array; The first liquid crystal initial alignment layer, the first electrical isolation layer, the patterned electrode layer, the first substrate and the first infrared anti-reflection film on the upper surface of the liquid crystal material layer, and are arranged in sequence on the lower surface of the liquid crystal material layer The second liquid crystal initial alignment layer, the second electrical isolation layer, the common electrode layer, the second substrate and the second infrared anti-reflection film; the common electrode layer is composed of a layer of homogeneous conductive film; the patterned electrode layer It is composed of sub-electrodes distributed in an m×n array, and each sub-electrode is composed of a square or rectangular conductive film, wherein m and n are both integers greater than 1; the electronically controlled liquid crystal phase modulation microcolumn array is divided into m Electronically controlled liquid crystal phase modulation microcolumns distributed in an array of × n elements, the electronically controlled liquid crystal phase modulation microcolumns correspond to the sub-electrodes one by one, each sub-electrode is located in the center of the corresponding electronically controlled liquid crystal phase modulation microcolumn, forming The upper electrode of the electronically controlled liquid crystal phase modulation microcolumn, and the lower electrodes of all the electronically controlled liquid crystal phase modulation microcolumns are provided by the common electrode layer; The ratio is the electrode filling factor, and the electrode filling factor is 50% to 95%. the

Preferably, the chip further includes a chip housing; the electronically controlled liquid crystal phase modulation microcolumn array is packaged in the chip housing and fixedly connected to the chip housing, and its light incident surface and light exit surface pass through the chip housing. The openings facing the front and rear end faces are exposed; the side of the chip housing is provided with a plurality of input ports for driving and controlling signals. the

Preferably, the first to eighth drive control signal input ports are provided on the side of the chip housing; the upper electrodes of each electronically controlled liquid crystal phase modulation microcolumn are independently drawn out through a wire, and these upper electrode leads are grouped into all The first to eighth drive control signal input ports are described above; the common electrode layer is led out through eight wires, and the eight common electrode layer lead wires are respectively connected to the first to eighth drive control signal input ports; each drive control The upper electrode leads and the common electrode layer leads in the signal input port are respectively located at the two ends of the port. the

Generally speaking, compared with the prior art, the above technical solution conceived by the utility model has the following beneficial effects:

1. Beam construction, beam steering and beam scanning based on phase modulation. The utility model constructs the specific shape and direction of the infrared beam based on the wavefront modulation through the electronically controlled liquid crystal phase modulation microcolumn array. the

2. The control method is flexible. By performing an independent power-on operation on each electronically controlled liquid crystal phase modulating microcolumn in the electronically controlled liquid crystal phase modulating microcolumn array, the light wave phase distribution form can be flexibly constructed, which has the advantage of flexible control methods. the

3 intelligent. The shaping and modulating operation of the infrared outgoing wave field by modulating the frequency or amplitude of the driving voltage signal loaded on the electronically controlled liquid crystal phase-modulating microcolumn array can be constrained or intervened by prior knowledge or beam effect Or under the guidance of intelligent features. the

4. High control precision. Since the utility model adopts a liquid crystal phase modulation structure that can be precisely electrically driven and controlled, it has extremely high stability and control precision of structure, electricity, and electro-optic parameters. the

5. Easy to use. The main body of the chip of the utility model is an electronically controlled liquid crystal phase modulation microcolumn array packaged in the chip shell, which is convenient to connect and plug in the infrared light path, and is easy to match and couple with conventional infrared optical photoelectric structures, electronic and mechanical devices, and the like. the

Description of drawings

Figure 1 (a), (b) is a schematic structural view of the infrared liquid crystal phased array chip of the embodiment of the utility model;

Fig. 2 is the structure schematic diagram of electronically controlled liquid crystal phase modulation microcolumn array;

Fig. 3 is a schematic diagram of light wave conversion of an infrared liquid crystal phased array chip according to an embodiment of the present invention. the

In all the drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1-first driving signal input port, 2-second driving signal input port, 3-third driving signal input Port, 4-fourth drive control signal input port, 5-fifth drive control signal input port, 6-sixth drive control signal input port, 7-seventh drive control signal input port, 8-eighth drive control signal input port Port, 9-electronically controlled liquid crystal phase modulation microcolumn array, 10-chip shell. the

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute conflicts with each other. the

As shown in Fig. 1 (a) and (b), the infrared liquid crystal phased array chip of the embodiment of the present invention includes a chip shell 10 and an electronically controlled liquid crystal phase modulation microcolumn array 9 . The electronically controlled liquid crystal phase modulation microcolumn array 9 is packaged in the chip case 10 and is fixedly connected with the chip case 10 , and its light incident surface and light exit surface are exposed through the facing openings on the front and rear end faces of the chip case 10 . The side surfaces of the chip housing 10 are provided with first to eighth control signal input ports 1 to 8 , wherein two control signal input ports are provided on each side. the

As shown in Figure 2 and Figure 3, the electronically controlled liquid crystal phase modulation microcolumn array 9 includes a liquid crystal material layer, a first liquid crystal initial alignment layer, a first electrical isolation layer, a patterned electrode layer, The first substrate and the first infrared anti-reflection film, and the second liquid crystal initial alignment layer, the second electrical isolation layer, the common electrode layer, the second substrate and the second infrared anti-reflection film arranged in sequence on the lower surface of the liquid crystal material layer . The common electrode layer is composed of a layer of homogeneous conductive film. The patterned electrode layer is composed of sub-electrodes distributed in an m×n array, and each sub-electrode is composed of a micro-square or micro-rectangular conductive film, wherein m and n are both integers greater than 1. the

Preferably, the material of the patterned electrode layer and the common electrode layer is gold or aluminum, and its thickness is in the range of tens to hundreds of nanometers. The first substrate and the second substrate are made of the same optical material. The first and second electrical isolation layers are made of an electrically insulating film material with high infrared transmittance, typically SiO ₂ film, etc., and their thickness is also in the range of tens to hundreds of nanometers. The electrical isolation layer is used to block the carrier (such as electrons, etc.) overflowing from the material of the patterned electrode layer and the common electrode layer to enter the channel of the liquid crystal material layer through the initial alignment layer of the liquid crystal, preventing its polarity with the liquid crystal molecules The groups neutralize each other and cause the liquid crystal material to fail.

Divide the above-mentioned electronically controlled liquid crystal phase modulation microcolumn array 9 into electronically controlled liquid crystal phase modulation microcolumns distributed in an m×n element array. Control the center of the liquid crystal phase modulation microcolumn to form the upper electrode of the electronically controlled liquid crystal phase modulation microcolumn, and the lower electrodes of all the electronically controlled liquid crystal phase modulation microcolumns are provided by the common electrode layer. The ratio of the area of a single sub-electrode to the light-receiving area of the corresponding electrically controlled liquid crystal phase modulation microcolumn is called the electrode fill factor, and its typical value is between 50% and 95%. the

When working, each electronically controlled liquid crystal phase-modulating micro-column is powered and controlled independently. Specifically, the upper electrodes of each electronically controlled liquid crystal phase modulation microcolumn are independently drawn out through a wire, and these upper electrode leads are grouped into the first to eighth drive control signal input ports 1 to 8, and the common electrode layer Lead out through eight wires, connect the eight common electrode layer leads to the first to eighth drive control signal input ports 1 to 8 respectively, and the upper electrode leads and common electrode layer lead wires in each drive control signal input port are respectively located at both ends of the port. According to the position of each electronically controlled liquid crystal phase modulation microcolumn in the electronically controlled liquid crystal phase modulation microcolumn array 9, each electronically controlled liquid crystal phase modulation microcolumn is addressable through the first to eighth drive signal input ports 1 to 8 The driving control voltage signal is loaded. As shown in Figure 2, for the electronically controlled liquid crystal phase modulating microcolumn in the sixth row nth column in the electronically controlled liquid crystal phase modulating microcolumn array 9, the driving voltage signal loaded on it is denoted as V _6n , for the electronically controlled liquid crystal The electronically controlled liquid crystal phase-modulating microcolumns in the mth row and nth column in the phase-modulating microcolumn array 9 are denoted as V _mn by the driving voltage signal applied thereto.

The infrared liquid crystal phased array chip of the embodiment of the utility model can be directly placed in the test light path, or can be placed at the focal plane of the infrared optical system composed of the main mirror or configured with weak defocus. It works as follows. the

Through the upper electrode leads and the patterned electrode layer leads in the first to eighth drive control signal input ports 1 to 8, the drive voltage signal V _ij is loaded on the electronically controlled liquid crystal phase modulation microcolumn in the i-th row and j-th column , so that each electronically controlled liquid crystal phase modulation microcolumn is independently powered and driven, wherein, i=1, 2, ..., m, j = 1, 2, ..., n. The liquid crystal molecules distributed near the inner surface of the double-layer planar electrode plate (including infrared anti-reflection film, substrate, electrode layer, electrical isolation layer and liquid crystal initial alignment layer) that constitute the liquid crystal microcavity are fabricated on two opposite planar electrodes. The liquid crystal initial alignment layer with parallel groove orientation on the surface of the plate is firmly anchored, and the driving voltage signal higher than the threshold value of the liquid crystal material driving signal will excite an adjustable space electric field in the liquid crystal material, and in the liquid crystal material layer The liquid crystal molecules are driven by the space electric field excited by the double-layer planar electrode plates to form a specific refractive index distribution.

After the infrared incident light wave enters the electronically controlled liquid crystal phase modulation microcolumn array, the electronically controlled liquid crystal phase modulation microcolumn array divides the infrared incident light wave into arrayed sub-planes according to the array scale and arrangement of the electronically controlled liquid crystal phase modulation microcolumn The incident wavefront, the incident wavefront of each sub-plane interacts with the liquid crystal molecules in a specific refractive index distribution under the control of the electric field to form an arrayed sub-plane outgoing wavefront with a specific degree of phase delay, and the arrayed sub-plane exits The wavefronts are coupled to form outgoing wavefronts that are output from the chip. the

As shown in Figure 3, the refraction of the liquid crystal molecules in the liquid crystal material layer is modulated by adjusting the frequency or mean square amplitude of the driving voltage signal V _ij loaded on the electronically controlled liquid crystal phase-modulating microcolumn in the i-th row and j-column. The distribution shape of the rate makes the optical path of the light wave passing through the liquid crystal material layer change due to the change of the refractive index, and then causes the outgoing wavefront of each sub-plane to produce a certain degree of phase delay adjusted by the driving voltage signal, and the outgoing wavefront of each sub-plane is coupled An outgoing wavefront is formed to obtain an outgoing beam based on a specific shape of the outgoing wavefront. The shape change of the output optical wavefront constrains operations such as beam forming, beam shape modulation, beam steering, or beam scanning. Specifically, after loading the electronic driving control signal to the chip, the arrayed phase adjustment function of the chip can flexibly construct the beam shape, and perform operations such as electronically controlled beam expansion, beam shrinkage, beam divergence, beam focusing, beam steering, or beam scanning. . For target or ambient light field disturbances and electrical parameter fluctuations, the optical parameters of the outgoing beam can be calibrated by timely modulating the multi-channel parallel driving voltage signals loaded on the chip, and the chip has anti-disturbance capabilities. After the chip is powered off, the arrayed phase modulation function disappears, and the beam characteristics of the light wave remain unchanged after passing through the chip.

Those skilled in the art can easily understand that the above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements and modifications made within the spirit and principles of the utility model Improvements and the like should all be included within the protection scope of the present utility model. the

Claims (3)

1. an infra-red liquid crystal phased array chip, is characterized in that, comprises electrically-controlled liquid crystal phase modulation micro-pillar array; Described electrically-controlled liquid crystal phase modulation micro-pillar array comprises liquid crystal material layer, be successively set on the first liquid crystal initial orientation layer of described liquid crystal material layer upper surface, the first electricity isolated layer, patterned electrodes layer, the first substrate and the first infrared anti-reflection film, and be successively set on the second liquid crystal initial orientation layer of described liquid crystal material layer lower surface, the second electricity isolated layer, common electrode layer, the second substrate and the second infrared anti-reflection film; Described common electrode layer is made up of the homogeneous conducting film of one deck; The sub-electrode that described patterned electrodes layer is distributed by m × n element array is formed, and each sub-electrode is formed by square or rectangular conducting film, and wherein, m, n are the integer being greater than 1;

Described electrically-controlled liquid crystal phase modulation micro-pillar array is divided into the electrically-controlled liquid crystal phase modulation microtrabeculae of m × n element array distribution, described electrically-controlled liquid crystal phase modulation microtrabeculae and described sub-electrode one_to_one corresponding, each sub-electrode is all positioned at the center of corresponding electrically-controlled liquid crystal phase modulation microtrabeculae, form the top electrode of electrically-controlled liquid crystal phase modulation microtrabeculae, the bottom electrode of all electrically-controlled liquid crystal phase modulation microtrabeculaes is provided by described common electrode layer; The area of single sub-electrode is electrode activity coefficient with the ratio of the light receiving area of corresponding electrically-controlled liquid crystal phase modulation microtrabeculae, and described electrode activity coefficient is 50% ~ 95%.

2. infra-red liquid crystal phased array chip as claimed in claim 1, it is characterized in that, described chip also comprises chip carrier; Described electrically-controlled liquid crystal phase modulation micro-pillar array to be encapsulated in described chip carrier and to be connected with described chip carrier, its light entrance face and light-emitting face outside exposed by perforate just right on former and later two end faces of described chip carrier; The side of described chip carrier is provided with multiplely drives control signal input port.

3. infra-red liquid crystal phased array chip as claimed in claim 2, it is characterized in that, the side of described chip carrier is provided with first and drives control signal input port to the 8th; The top electrode of each electrically-controlled liquid crystal phase modulation microtrabeculae is all independently drawn by a wire, and these top electrodes lead-in wire grouping access described first drives control signal input port to the 8th; Described common electrode layer is drawn by eight wires, and these eight common electrode layer lead-in wires access described first respectively and drive control signal input port to the 8th; Each top electrode driven in control signal input port goes between and common electrode layer goes between lays respectively at the two ends of this port.