Environment sensor

• US 20050008061A1
• Filed: 07/08/2004
• Published: 01/13/2005
• Est. Priority Date: 07/10/2003
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Kaneko, Norio
• Granted Patent: US 7,114,848 B2
• Time in Patent Office: Days
• US Class Current: 374/16
• CPC Class Codes: G01N 27/048 for determining moisture content of the material

Abstract

An environment sensor (11) for measuring the temperature and humidity can be miniaturized and can respond at high speed. The environment sensor (11) includes a temperature sensing portion (111) having a temperature-sensitive material (1) made of a metal oxide, and a humidity-sensing portion (112) which is formed on the same substrate as the temperature sensing portion (111) and measures the ambient humidity by using a change in electrical characteristics. At least one of a pair of electrodes (2, 3) of the temperature sensor (111) is integrated with an electrode of the humidity-sensing portion (112).

Claims

1. An environment sensor comprising:

a temperature sensor containing a temperature-sensitive material made of a metal oxide; and

a humidity sensor which measures an ambient humidity by using a change in electrical characteristic,

wherein at least one of a pair of electrodes of said temperature sensor is integrated with an electrode of said humidity sensor.

2. The sensor according to claim 1, wherein the metal oxide is a ferroelectric.

3. The sensor according to claim 1, wherein the metal oxide is a pyroelectric.

4. The sensor according to claim 3, wherein the metal oxide has a perovskite structure.

5. The sensor according to claim 1, wherein said temperature sensor and humidity sensor are formed on the same substrate, and at least one of a portion of said substrate in a formation region of said temperature sensor and a portion of said substrate in a formation region of said humidity sensor is removed.

6. An environment sensor comprising:

a temperature sensor which measures a temperature; and

a humidity sensor which measures a humidity,

wherein said temperature sensor and humidity sensor are formed on the same substrate as a pair of stacked bodies having a multilayered structure including a lower electrode, a metal oxide layer formed on the lower electrode, and an upper electrode formed on the metal oxide layer, and

the lower electrode of said temperature sensor and the lower electrode of said humidity sensor are common, and the upper electrode of said temperature sensor and the upper electrode of said humidity sensor are common.

7. The sensor according to claim 6, wherein of at least the upper electrode of the stacked bodies which faces a measurement ambient, the upper electrode of said temperature sensor covers a whole upper surface of the metal oxide layer, and the upper electrode of said humidity sensor partially covers the metal oxide layer.

8. The sensor according to claim 6, wherein the metal oxide layer of at least said temperature sensor contains a material selected from the group consisting of a ferroelectric and pyroelectric.

9. The sensor according to claim 8, wherein the metal oxide has a perovskite structure.

10. The sensor according to claim 6, wherein at least one of a portion of said substrate in a formation region of said temperature sensor and a portion of said substrate in a formation region of said humidity sensor is removed.

11. An apparatus for measuring an environment, comprising:

an environment sensor including a temperature sensor in which a temperature-sensitive material for sensing a temperature is made of a metal oxide, and a humidity sensor in which a humidity-sensitive material for measuring a humidity is made of a conductor having a function of at least one of an electrode and signal line of said temperature sensor;

a signal detecting/processing unit which detects and processes an output signal from said environment sensor; and

a transmitting unit which transmits an output processing result from said signal detecting/processing unit to an external apparatus by radio.

12. An apparatus for measuring an environment, comprising:

an environment sensor including a temperature sensor which measures a temperature, and a humidity sensor which measures a humidity, said temperature sensor and humidity sensor being formed on the same substrate as a pair of stacked bodies having a multilayered structure including a lower electrode, a metal oxide layer formed on the lower electrode, and an upper electrode formed on the metal oxide layer, and said pair of stacked bodies being connected in series;

a signal detecting/processing unit which detects and processes an output signal from said environment sensor; and

a transmitting unit which transmits an output processing result from said signal detecting/processing unit to an external apparatus by radio.

13. The apparatus according to claim 12, wherein said signal detecting/processing unit comprises a first signal detector for measuring an electrical characteristic of at least one of the lower electrode and upper electrode, and a second signal detector for measuring an electrical characteristic between the lower electrode and upper electrode, and processes signals from said first and second signal detectors.

14. An environment measurement system comprising:

not less than one environment measurement apparatus cited in claim 12 arranged at an arbitrary position in an arbitrary space; and

a unit which collects a measurement result from said environment measurement apparatus and performs predetermined processing, thereby measuring distributions of a temperature and humidity in the space and changes in temperature and humidity with time.