ACTIVE TERAHERTZ IMAGER

• US 20140326890A1
• Filed: 04/30/2014
• Published: 11/06/2014
• Est. Priority Date: 05/02/2013
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Debray, Alexis, Sekiguchi, Ryota
• Granted Patent: US 9,797,778 B2
• Time in Patent Office: Days
• US Class Current: 250/349
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 2005/106 Arrays
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 5/10 using electric radiation detectors
• CPC Class Codes: G01N 21/3581 using far infrared light; using Terahertz radiation

Abstract

An imager for obtaining an image of an object includes a substrate including a plurality of electrical emitting units for emitting electromagnetic waves and a plurality of electrical detecting units for detecting the electromagnetic waves reflected by the object. Each emitting unit includes an electrical emitter, a first antenna, a first metallic reflector, and a first dielectric element between the first antenna and the first metallic reflector. Each detecting unit includes an electrical detector, a second antenna, a second metallic reflector, and a second dielectric element between the second antenna and the second metallic reflector.

Claims

1. An imager for obtaining an image of an object, comprising:

a substrate including a plurality of electrical emitting units configured to emit electromagnetic waves and a plurality of electrical detecting units configured to detect the electromagnetic waves reflected by the object,

wherein each emitting unit includes an electrical emitter, a first antenna, a first metallic reflector, and a first dielectric element between the first antenna and the first metallic reflector, and

wherein each detecting unit includes an electrical detector, a second antenna, a second metallic reflector, and a second dielectric element between the second antenna and the second metallic reflector.

10. The imager according to claim 1, wherein a distance between two consecutive detectors is less than twice the wavelength of the electromagnetic waves.

11. The imager according to claim 1, wherein the electromagnetic waves include THz radiations.

12. The imager according to claim 1, wherein the first and second metallic reflectors are made of the same material.

13. The imager according to claim 1, wherein the first and second dielectric elements are made of the same material.

14. The imager according to claim 1, wherein the first and second antennas are made of the same material.

15. The imager according to claim 1, wherein each emitter includes a differential negative resistance element.

16. The imager according to claim 1, wherein each emitter includes a resonant tunneling diode.

17. The imager according to claim 1, wherein each emitter includes a Quantum Cascade Laser.

18. The imager according to claim 1, wherein each detector includes a rectifier.

19. The imager according to claim 18, wherein the rectifier is a Schottky barrier diode.

2. An imager for obtaining an image of an object, comprising:

a first substrate including a plurality of electrical emitting units configured to emit electromagnetic waves; and

a second substrate including a plurality of electrical detecting units configured to detect the electromagnetic waves reflected by the object,

wherein each emitting unit includes an electrical emitter, a first antenna, a first metallic reflector, and a first dielectric element between the first antenna and the first metallic reflector,

wherein each detecting unit includes an electrical detector, a second antenna, a second metallic reflector, and a second dielectric element between the second antenna and the second metallic reflector,

wherein one of the first and second substrates includes a plurality of channels passing through the substrate, and

wherein the first and second substrates are assembled such that the plurality of channels face the plurality of emitting units or detecting units.

3. The imager according to claim 2, wherein the plurality of channels is filled with a material same as a material of the first dielectric element.

4. The imager according to claim 2, wherein the walls of the plurality of channels are coated with a metallic layer.

7. The imager according to claim 2, wherein the thickness of the substrate including plurality of channels is less than 100 μ

m.

8. The imager according to claim 2, wherein the plurality of channels are formed by etching by KOH.

9. The imager according to claim 2, wherein the plurality of channels are formed by etching by TMAH.

5. An imager for obtaining an image of an object, comprising:

a first substrate including a plurality of electrical emitting units configured to emit electromagnetic waves; and

a second substrate including a plurality of electrical detecting units configured to detect the electromagnetic waves reflected by the object,

wherein each emitting unit includes an electrical emitter, a first antenna, a first metallic reflector, and a first dielectric element between the first antenna and the first metallic reflector,

wherein each detecting unit includes an electrical detector, a second antenna, a second metallic reflector, and a second dielectric element between the second antenna and the second metallic reflector,

wherein one of the first and second substrates includes a plurality of channels passing therethrough,

wherein the other of the first and second substrates includes a plurality of pillars,

wherein each emitting unit or detecting unit is formed on the top of each channel, and

wherein the first and second substrates are assembled such that the plurality of pillars fits into the plurality of channels.

6. The imager according to claim 5, further comprising insulating elements bridge the top of the pillars with a top surface of the one of the first and second substrates including the plurality of channels.