Abstract: A display apparatus includes an optical engine and a stack of expander devices. The optical engine forms input light which comprises a plurality of input light beams representing an input image. The stack of expander devices forms output light by diffractively expanding the input light. The output light includes a plurality of output light beams representing the input image. The stack includes a first expander device and a second expander device. The grating period of each diffractive element of the first expander device is equal to the grating period of a corresponding diffractive element of the second expander device.

Abstract: An electromagnetic ultrasonic double wave transducer, comprising a shell (1), and a permanent magnet assembly, a coil (4), a shielding layer (5), and a wire (6) which are provided in the shell (1). The permanent magnet assembly comprises a first permanent magnet (2) and a second permanent magnet (3) sleeved on the first permanent magnet (2). The magnetizing directions of the first permanent magnet (2) and the second permanent magnet (3) are perpendicular to the bottom of the shell (1), and the magnetic field directions of the first permanent magnet (2) and the second permanent magnet (3) are opposite. A non-conducting non-magnetic bushing material (9) is provided between the first permanent magnet (2) and the second permanent magnet (3), and upper end faces of the first permanent magnet (2) and the second permanent magnet (3) realize magnetic circuit closing by means of a magnetic circuit closing element (8).

Abstract: An optical device comprises a waveguide plate comprising an entrance pupil grating unit, a left pupil-expanding grating unit, and a right pupil-expanding grating unit. The left and right pupil-expanding grating units are bilaterally symmetric, and left and right exit pupil grating units are bilaterally symmetric. An input light is diffracted by the entrance pupil grating unit to form a first left guided light and a first right guided light, the first left guided light is diffracted by the left pupil-expanding grating unit to form a second left guided light, and the first right guided light is diffracted by the right pupil-expanding grating unit to form a second right guided light. The second left guided light is diffracted by the left pupil-expanding grating unit to form a left output light, and the second right guided light is diffracted by the right pupil-expanding grating unit to form a right output light.

Abstract: A display apparatus comprises an optical engine, a modifying unit, and a diffractive waveguiding expander device. The optical engine is configured to form first input light, which comprises a plurality of input light beams representing an input image. The modifying unit is configured to form second input light from the first input light. The diffractive waveguiding expander device is configured to form output light by diffractively expanding the second input light, where the output light comprises a plurality of output light beams representing said input image. The modifying unit contain at least one prism, which compensates the angular dispersion between the plurality of output light beams caused by the possibly exists imperfection of the waveguiding expander device.

Abstract: A display apparatus (500) for displaying a virtual image (VIMG1) comprises: an optical engine (ENG1) to form input light (IN1), which represents an input image (IMG0), an expander device (EPE1) to form light beams (B3P0,R,B3P1,R) of output light (OUT1) by expanding light beams (B0P0,R,B0P1,R) of the input light (IN1), the expander device (EPE1) comprising: a waveguide plate (SUB1), a diffractive in-coupling element (DOE1) to form first guided light (B1a) and second guided light (B1b) by coupling input light (IN1) into the waveguide plate (SUB1), wherein the display apparatus (500) comprises a base (BASE1) and an actuating mechanism (MOTOR1) to cause rotary motion of the expander device (500) with respect to the base (BASE1), wherein an angle (?1) between an optical axis (AX0) of the optical engine (ENG1) and the axis (AX1) of rotation of the expander device (500) is in the range of 10° to 45°.

Abstract: A display apparatus for displaying a virtual image (VIMG1) includes a rotating expander device (EPE1) to form light beams (B3P0,R,B3P1,R) of output light (OUT1) by expanding light beams (B0P0,R,B0P1,R) of input light (IN1), the expander device (EPE1) includes: a waveguide plate (SUB1), an in-coupling element (DOE1) to form first guided light (B1a) and second guided light (B1c) by coupling input light (IN1) into the waveguide plate (SUB1), a first out-coupling element (DOE3a) to form output light (OUT1) by coupling the first guided light (B1a) out of the waveguide plate (SUB1), and a second out-coupling element (DOE3c) to form output light (OUT1) by coupling the second guided light (B1c) out of the waveguide plate (SUB1). The in-coupling element (DOE1) has a first input grating vector (V1a) and a second input grating vector (V1c), and an angle (?1ac) between the first and second input grating vectors is between 60° and 120°.

Abstract: An optical device (EPE1) comprises a waveguide plate (SUB1) comprising an in-coupling element (DOE1), a first expander element (DOE2a), a second expander element (DOE2b) and an out-coupling element (DOE3), wherein the out-coupling element (DOE3) is arranged to form combined output light (OUT1) by combining the first output light (OB3a) with the second output light (OB3b), wherein the in-coupling element (DOE1) has a first grating period (d1a) for forming the first guided light (B1a), and wherein the in-coupling element (DOE1) has a second different grating period (d1b) for forming the second guided light (B1b), wherein the optical device (EPE1) comprises a first spectral filter region (C2a) to prevent coupling of red light from the in-coupling element (DOE1) to the out-coupling element (DOE3) via the first expander element (DOE2a). The optical device (EPE1) can display a color image with an extended field of view.

Abstract: A diffractive beam expander device (EPE1) includes a first spectral filter region (C2a) and a second spectral filter region (C2b) to provide a first optical route for blue and green light (B, G), and to provide a second optical router for red light (R). The expander device (EPE1) includes a first Bragg grating region (BRGa) to enhance optical absorption of red light (R) in the first spectral filter region (C2a). The expander device (EPE1) includes a second Bragg grating region (BRGb) to enhance optical absorption of blue light (B) in the second spectral filter region (C2b).

Abstract: Disclosed are an optical expander apparatus, and a display apparatus. The optical expander apparatus comprises a waveguide plate, which in turn comprises: an in-coupling element to form first guided light by diffracting input light, a beam-split element to form second guided light by diffracting the first guided light, a first expander element to form third guided light by diffracting the second guided light, a second expander element to form fourth guided light by diffracting the first guided light, and an out-coupling element to form first output light by diffracting the third guided light, and to form second output light by diffracting the fourth guided light, wherein the out-coupling element is arranged to form combined output light by combining the first output light with the second output light, wherein the beam-split element has a same first grating period as the first expander element, and the second expander element has a different second grating period from the first expander element.

Abstract: A display apparatus (500) for displaying a virtual image (VIMG1) includes an expander device (EPE1) to form light beams (B3P1,R, B3P2,R) of output light (OUT1) by expanding light beams (B0P1,R, B0P2,R) of input light (IN1), the expander device (EPE1) including a waveguide plate (SUB1), an in-coupling element (DOE1) to form guided light (B1) by coupling input light (IN1) into the waveguide plate (SUB1), and an out-coupling element (DOE3) to form output light (OUT1) by coupling the guided light (B1) out of the waveguide plate (SUB1), wherein the display apparatus (500) includes a base (BASE1) and an actuating mechanism (MOTOR1) to cause rotary and/or oscillatory motion of the waveguide plate (SUB1) with respect to the base (BASE1).

Abstract: An optical device comprises a waveguide plate, which in turn comprises: an in-coupling element to form first guided light and second guided light by diffracting input light, first expander element to form third guided light by diffracting the first guided light, second expander element to form fourth guided light by diffracting the second guided light, and an out-coupling element to form first output light by diffracting the third guided light, and to form second output light by diffracting the fourth guided light, wherein the out-coupling element is arranged to form combined output light by combining the first output light with the second output light, wherein the in-coupling element has a first grating period for forming the first guided light, and wherein the in-coupling element has a second different grating period for forming the second guided light.

Abstract: A diffractive beam expander device (EPE1) includes a first spectral filter region (C2a) and a second spectral filter region (C2b) to provide a first optical route for blue and green light (B, G), and to provide a second optical router for red light (R). The expander device (EPE1) includes a first Bragg grating region (BRGa) to enhance optical absorption of red light (R) in the first spectral filter region (C2a). The expander device (EPE1) includes a second Bragg grating region (BRGa) to enhance optical absorption of blue light (B) in the second spectral filter region (C2b).

Abstract: An optical device comprises a waveguide plate comprising an entrance pupil grating unit, a left pupil-expanding grating unit, and a right pupil-expanding grating unit. The left and right pupil-expanding grating units are bilaterally symmetric, and left and right exit pupil grating units are bilaterally symmetric. An input light is diffracted by the entrance pupil grating unit to form a first left guided light and a first right guided light, the first left guided light is diffracted by the left pupil-expanding grating unit to form a second left guided light, and the first right guided light is diffracted by the right pupil-expanding grating unit to form a second right guided light. The second left guided light is diffracted by the left pupil-expanding grating unit to form a left output light, and the second right guided light is diffracted by the right pupil-expanding grating unit to form a right output light.

Abstract: This invention relates to an optical expander device with its display device, and a method of light output and image display, including a waveguide plate, the first optical diffractive in-coupling element, the first retrieval unit, the second retrieval unit, the second optical diffractive expander element, the third optical diffractive expander element, and the fourth optical diffractive out-coupling element. The fourth optical diffractive out-coupling element forms part of the first output light (OB4), by diffracting guided light, the third retrieval light (B3a), and the fourth retrieval light (B4a) to the same direction; simultaneously, the fourth optical diffractive out-coupling element diffracts the first direct-through light (B1b) and the second direct-through light (B2b) to the same direction, forming the other part of the first output light (OB4). This device of the present disclosure may greatly improve the uniformity of the intensity distribution of the output light.

Abstract: An optical device (EPE1) comprises a waveguide plate (SUB1) comprising an in-coupling element (DOE1), a first expander element (DOE2a), a second expander element (DOE2b) and an out-coupling element (DOE3), wherein the out-coupling element (DOE3) is arranged to form combined output light (OUT1) by combining the first output light (OB3a) with the second output light (OB3b),wherein the in-coupling element (DOE1) has a first grating period (d1a) for forming the first guided light (B1a), and wherein the in-coupling element (DOE1) has a second different grating period (d1b) for forming the second guided light (B1b),wherein the optical device (EPE1) comprises a first spectral filter region (C2a) to prevent coupling of red light from the in-coupling element (DOE1) to the out-coupling element (DOE3) via the first expander element (DOE2a).The optical device (EPE1) can display a color image with an extended field of view.

Abstract: Disclosed are a data disaster recovery storage device and a carrier. The data disaster recovery storage device comprises: a housing; a fire-resistant shell; a liner; an internal data line; and a memory. The memory is connected to the internal data line, and is suspended inside the liner. The water absorption resin is filled at the outer side of the memory. According to the present invention, a plurality of thermal insulation and heat-dissipation means are used for ensuring the safety of the memory during vehicle burning. The memory is mounted in a suspended manner, and is not in direct contact with other structures, which can effectively avoid direct heat conduction, and effectively perform shock absorbing. The invention utilizes the property that water boils at a constant temperature under the standard atmospheric pressure, and uses a method for storing water in a liner shell to ensure that the memory is not damaged at a certain external high temperature within a certain period of time.

Abstract: An optical device comprises a waveguide plate, which in turn comprises: an in-coupling element to form first guided light and second guided light by diffracting input light, first expander element to form third guided light by diffracting the first guided light, second expander element to form fourth guided light by diffracting the second guided light, and an out-coupling element to form first output light by diffracting the third guided light, and to form second output light by diffracting the fourth guided light, wherein the out-coupling element is arranged to form combined output light by combining the first output light with the second output light, wherein the in-coupling element has a first grating period for forming the first guided light, and wherein the in-coupling element has a second different grating period for forming the second guided light.

Abstract: A optical device includes a waveguide plate, which includes an in-coupling element to form first guided light (B1) and a second guided light (B2) by diffracting input light (IN1), an expander element to form third guided light (B3) by diffracting the first guided light (B1), an out-coupling element to form first output light (OB3) by diffracting the third guided light (B3), a bypass element to form fourth guided light (B4) by diffracting the second guided light (B2), wherein the first guided light (B1) propagates in a first direction, the second guided light (B2) propagates in a second direction, and the angle ?12 between the first direction) and the second direction is in the range of 60° to 120°, wherein the out-coupling element includes one or more augmenting regions.

Abstract: This invention relates to an optical expander device with its display device, and a method of light output and image display, including a waveguide plate, the first optical diffractive in-coupling element, the first retrieval unit, the second retrieval unit, the second optical diffractive expander element, the third optical diffractive expander element, and the fourth optical diffractive out-coupling element. The fourth optical diffractive out-coupling element forms part of the first output light (OB4), by diffracting guided light, the third retrieval light (B3a), and the fourth retrieval light (B4a) to the same direction; simultaneously, the fourth optical diffractive out-coupling element diffracts the first direct-through light (B1b) and the second direct-through light (B2b) to the same direction, forming the other part of the first output light (OB4). This device of the present disclosure may greatly improve the uniformity of the intensity distribution of the output light.

Abstract: An optical waveguide detector is provided, which includes: a silicon waveguide layer and a germanium waveguide layer. The germanium waveguide layer includes a first heavily germanium-doped area and a germanium-undoped area. A first surface of the germanium waveguide layer includes a surface of the first heavily germanium-doped area, and the first surface is a surface of the germanium waveguide layer away from the silicon waveguide layer in the first direction. A width of the first heavily germanium-doped area is less than or equal to half a width of the first surface, and a thickness of the first heavily germanium-doped area is greater than or equal to 5 nm and less than or equal to 200 nm. According to embodiments, a bandwidth of the optical waveguide detector can be effectively increased.