Two-dimensional light modulating device and electronic apparatus including the same

Patent metadata

Field	Value
Publication number	US-10705406-B2
Application number	US-201715815188-A
Country	US
Kind code	B2
Filing date	Nov 16, 2017
Priority date	Nov 16, 2016
Publication date	Jul 7, 2020
Grant date	Jul 7, 2020

Abstract

A two-dimensional (2D) light modulating device may include a plurality of phase modulating elements and a circuit board. The plurality of phase modulating elements may include a meta surface having a nano-structure. The circuit board may be configured to independently control electrical signals that are respectively transmitted to the plurality of phase modulating elements. The circuit board may include a plurality of pixel circuit units. Each of the plurality of pixel circuit units may include a transistor and a capacitor.

First claim

What is claimed is:

1. A two-dimensional ( 2 D) light modulating device comprising:
a plurality of phase modulating elements comprising a meta surface having a nano-structure; and
a circuit board configured to independently control electrical signals that are respectively transmitted to the plurality of phase modulating elements, and comprising a plurality of pixel circuit units, wherein each of the plurality of pixel circuit units comprises a transistor and a capacitor,
wherein each of the plurality of phase modulating elements comprises:
a metal layer that is electrically connected to a corresponding pixel circuit unit among the plurality of pixel circuit units;
an active layer disposed on the metal layer, the active layer having a refractive index that changes based on an electrical signal transmitted from the corresponding pixel circuit unit;
a conductive nano-antenna disposed on the active layer;
a first insulating layer disposed between the active layer and the conductive nano-antenna; and
a second insulating layer disposed between the metal layer and the active layer.

2. The 2D light modulating device of claim 1 , wherein the active layer comprises a carrier-variable region where a concentration of carriers changes based on an applied voltage.

3. The 2D light modulating device of claim 2 , wherein the carrier variable region in the active layer is adjacent to the first insulating layer.

4. The 2D light modulating device of claim 1 , wherein the active layer comprises at least one of transparent conductive oxide, transition metal nitride, lithium niobate (LiNbO 3 ), lithium tantalate (LiTaO 3 ), potassium tantalate niobate (KTN), lead zirconate titanate (PZT), and a polymer material having an electro-optic property.

5. The 2D light modulating device of claim 1 , wherein at least some of conductive nano-antennas of the plurality of phase modulating elements are electrically connected to each other, and
wherein a uniform electric potential is applied to the at least some of the conductive nano-antennas.

6. The 2D light modulating device of claim 1 , wherein active layers of the plurality of phase modulating elements are electrically connected to each other, and
wherein a uniform electric potential is applied to the active layers.

7. The 2D light modulating device of claim 1 , wherein the active layer comprises a carrier-variable region where a concentration of carriers changes based on an applied voltage, and
wherein the carrier variable region in the active layer is adjacent to the second insulating layer.

8. A two-dimensional (2D) light modulating device comprising:
a plurality of phase modulating elements comprising a meta surface having a nano-structure; and
a circuit board configured to independently control electrical signals that are respectively transmitted to the plurality of phase modulating elements, and comprising a plurality of pixel circuit units, wherein each of the plurality of pixel circuit units comprises a transistor and a capacitor,
wherein each of the plurality of phase modulating elements comprises:
a dielectric nano-antenna;
a metal layer that is separated from the dielectric nano-antenna and electrically connected to a corresponding pixel circuit unit among the plurality of pixel circuit units;
an active layer disposed above the metal layer, the active layer having a refractive index that changes based on an electrical signal from the corresponding pixel circuit unit; and
a transparent conductive layer disposed on the active layer.

9. The 2D light modulating device of claim 8 , wherein the refractive index of the active layer is less than a refractive index of the dielectric nano-antenna.

10. The 2D light modulating device of claim 9 , wherein the dielectric nano-antenna comprises a material having a dielectric constant that is equal to or greater than 10.

11. The 2D light modulating device of claim 8 , wherein transparent conductive layers of the plurality of phase modulating elements are electrically connected to each other, and
wherein a uniform electric potential is applied to the transparent conductive layers.

12. The 2D light modulating device of claim 8 , wherein the active layer, the transparent conductive layer, and the dielectric nano-antenna are sequentially arranged above the metal layer.

13. The 2D light modulating device of claim 12 , further comprising a spacer layer between the metal layer and the active layer, the spacer layer comprising a dielectric material.

14. The 2D light modulating device of claim 8 , wherein the dielectric nano-antenna, the active layer, and the transparent conductive layer are sequentially arranged above the metal layer.

15. The 2D light modulating device of claim 14 , wherein the active layer and the transparent conductive layer have a same shape as the dielectric nano-antenna when viewed from a plan view.

16. The 2D light modulating device of claim 14 , further comprising a spacer layer between the metal layer and the dielectric nano-antenna, the spacer layer comprising a dielectric material.

17. The 2D light modulating device of claim 1 , wherein the nano-structure has one of a circular shape, an oval shape, a polygonal shape, a cross shape, a star shape, and a shape in which two or more of the circular shape, the oval shape, the polygonal shape, the cross shape, and the star shape are combined.

18. A lidar device comprising:
a light source unit;
a two-dimensional (2D) light modulating device configured to steer light irradiated from the light source unit toward an object, the two-dimensional light modulating device comprising:
a plurality of phase modulating elements comprising a meta surface having a nano-structure, and
a circuit board independently controlling electrical signals that are respectively transmitted to the plurality of phase modulating elements, the circuit board comprising a plurality of pixel circuit units, and each of the plurality of pixel circuit units comprising a transistor and a capacitor,

wherein each of the plurality of phase modulating elements comprises:
a metal layer that is electrically connected to a corresponding pixel circuit unit among the plurality of pixel circuit units;
an active layer disposed on the metal layer, the active layer having a refractive index that changes based on an electrical signal transmitted from the corresponding pixel circuit unit;
a conductive nano-antenna disposed on the active layer;
a first insulating layer disposed between the active layer and the conductive nano-antenna; and
a second insulating layer disposed between the metal layer and the active layer; and

a sensor configured to receive the light that is steered by the 2D light modulating device, irradiated onto the object, and is reflected from the object.

19. A light modulating device comprising:
a circuit board comprising a pixel circuit unit configured to generate a control signal; and
a phase modulating element disposed on the pixel circuit unit and being configured to receive the control signal from the pixel circuit unit and modulate at least one of a phase, a direction, and a shape of incident light,
wherein the phase modulating element comprises:
a dielectric nano-antenna;
a metal layer that is separated from the dielectric nano-antenna and electrically connected to the pixel circuit unit;
an active layer disposed above the metal layer, the active layer having a refractive index that changes based on an electrical signal from the pixel circuit unit and
a transparent conductive la

Assignees

• Samsung Electronics Co Ltd

Inventors

• Kim Sunil
• Kim Jungwoo
• Lee Duhyun
• Shin Changgyun
• Choi Byounglyong

Classifications

• H01S3/0071

  Beam steering, e.g. whereby a mirror outside the cavity is present to change the beam direction · CPC title

• G02B26/06 Primary

  for controlling the phase of light (G02B26/08 takes precedence {, measuring optical phase difference G01J9/00}) · CPC title

• G01S7/4804

  Auxiliary means for detecting or identifying lidar signals or the like, e.g. laser illuminators · CPC title

• G02F1/0152

  using free carrier effects, e.g. plasma effect · CPC title

• G02F1/292 Primary

  by controlled diffraction or phased-array beam steering (controlled diffraction for optical switching G02F1/31) · CPC title