Use of a two- or three-dimensional barcode as a diagnostic device and a security device

1. A building security system comprising:

means for detecting human motion;

an imaging device configured to scan for a visible code in response to the detection of human motion by the detecting means; and

a security device configured to:

decipher the scanned code;

determine an authorization level associated with the deciphered code; and

provide the human with a level of access to the building commensurate with the authorization level,

wherein the security device is further configured to:

wirelessly transmit a code to a personal electronic device of the human; and

provide the human with access to the building only if the deciphered scanned code corresponds to the wirelessly transmitted code.

2. The system of claim 1 wherein the detecting means comprises an infrared motion detector.

3. The system of claim 1 wherein the imaging device comprises a camera configured to scan for the visible code in each of two perpendicular directions.

4. The system of claim 1 wherein the imaging device configured to scan for a visible code in response to the detection of human motion in a space within six feet of the imaging device.

5. The system of claim 1 wherein the visible code comprises a QR code.

6. The system of claim 1 , wherein a response of the security device to a security sensor signal is dependent upon the determined authorization level.

7. The building security system of claim 1 , wherein the imaging device is configured to scan for a visible code on a device worn by a moving human.

8. A method of operating a building security system, comprising the steps of:

detecting human motion near an imaging device of the security system;

in response to the detecting step, using an imaging device to scan for a visible code displayed in front of the imaging device;

deciphering the scanned code;

determining an authorization level associated with the deciphered code; and

providing the human with a level of access to the building commensurate with the authorization level, and

comprising the further steps of:

using the security device to wirelessly transmit a code to a personal electronic device of the human; and

using the security device to provide the human with access to the building only if the deciphered scanned code corresponds to the wirelessly transmitted code.

9. The method of claim 8 wherein the detecting step is performed by an infrared motion detector.

10. The method of claim 8 wherein the imaging device comprises a camera, the using step comprising using the camera to scan for the visible code in each of two perpendicular directions.

11. The method of claim 8 wherein the using step comprises using the imaging device to scan for a visible code in response to the detecting of human motion in a space within six feet of the imaging device.

12. The method of claim 8 wherein the visible code comprises a QR code.

13. The method of claim 8 , comprising the further step of using the security device to respond to a security sensor signal dependent upon the determined authorization level.

14. The method of claim 8 , further comprising:

determining at least one room where the human is not permitted based on the authorization level; and

activating an alarm when the human is detected in the at least one room where the human is not permitted.

15. The method of claim 14 , further comprising determining at least one room where the human is permitted based on the authorization level, and wherein the act of providing the human with a level of access to the building commensurate with the authorization level includes not activating the alarm when the human is detected in the at least one room where the human is permitted.

16. A building security system comprising:

a motion detector;

an imaging device configured to scan for a visible code on a personal electronic device carried by a human in response to detection of motion by the motion detector; and

a controller configured to:

wirelessly transmit a code to a personal electronic device of the human,

decipher a code displayed on the personal electronic device of the human using the imaging device,

determine an authorization level of access to the building based on the deciphered code, and

providing the human with the determined level of access to the building only if the deciphered code matches the wirelessly transmitted code.

17. The building security system of claim 16 , wherein the controller is further configured to

determine at least one room where the human is not permitted based on the authorization level, and

activate an alarm when the human is detected in the at least one room where the human is not permitted.

18. The building security system of claim 17 , wherein the controller is further configured to determine at least one room where the human is permitted based on the authorization level, and wherein the security device is configured to provide the human with the level of access to the building commensurate with the authorization level by not activating the alarm when the human is detected in the at least one room where the human is permitted.