Light measurement and/or control translation for daylighting

• US 9,804,024 B2
• Filed: 03/14/2014
• Issued: 10/31/2017
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: MoJo Labs Inc.
• Original Assignee: MoJo Labs Inc.
• Inventors: Jones, Morgan
• Primary Examiner(s): Luu, Thanh
• Assistant Examiner(s): Wyatt, Kevin
• Application Number:
  US14/214,024
• Publication Number:
  US 20140263977A1
• Time in Patent Office: 1,327 Days
• Field of Search: 250214 AL
• CPC Class Codes: G01J 1/0228 Control of working procedures; Failure detection; Spectral bandwidth calculation
• CPC Class Codes: G01J 1/16 using electric radiation detectors G01J1/20 takes precedence
• CPC Class Codes: G01J 1/4204 with determination of ambient light solar light G01J2001/4266
• CPC Class Codes: G01J 2001/0257 portable
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/115 by determining the presence or movement of objects or living beings
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

Systems and methods are disclosed to translate a desired light level at a particular task location to a light level measured by a light sensor at a non-task location such as a wall location or a light switch location. For example, the light measured on the wall may be used to accomplish daylighting energy savings while maintaining a relatively constant illuminance value at the task location. Alternatively or additionally, up/down button presses at the wall location may be used to provide constant or consistent illuminance changes at the task location.

Claims

1. A method for measuring the ambient task light level, the method comprising:

measuring a first ambient light level at a first location within an architectural space at a first time;

measuring a second ambient light level at a second location within the architectural space at a time near the first time, wherein the first location is different than the second location;

determining a non-task-to-task efficiency translation from the first ambient light level and the second ambient light level;

determining a third ambient light level at the second location at a second time, wherein the second time is different than the first time; and

determining a light adjustment value for illuminating the first location from the third ambient light level and the non-task-to-task efficiency translation, wherein determining the light adjustment value is determined from;

L_adjustment=L_{desired at first location}−

KL_{second location},

where L_adjustment is the light adjustment value, L_{desired at first location} is the desired light amount at the first location, K is the non-task-to-task efficiency translation, and L_{second location} is the second ambient light level at the second location.

2. The method according to claim 1, wherein the non-task-to-task ambient translation comprises a constant.

3. The method according to claim 1, wherein the non-task-to-task ambient translation comprises a table having a plurality of constants.

4. The method according to claim 1, wherein the determining a third ambient light level at the second location at a second time further comprises:

measuring a total light level at the second location;

determining the light contribution of one or more light fixtures to the light level at the second location; and

determining the third ambient light level from the total light level and the light contribution of the one or more light fixtures.

5. The method according to claim 1, wherein the non-task-to-task ambient translation is the ratio of the first ambient light level at the first location and the second ambient light level at the second location.

6. The method according to claim 1, wherein the first ambient light level is measured at a first location using a smart phone.

7. A light sensor comprising:

a photo sensor;

a memory; and

a controller coupled with the photo sensor and the memory, wherein the controller is configured to;

measure a first ambient light level using the photo sensor at a task location within an architectural space at a first time;

measure a second ambient light level using the photo sensor at a non-task location within the architectural space at a time near the first time, wherein the task location is different than the non-task location;

determine a non-task-to-task efficiency translation from the first ambient light level and the second ambient light level;

store the non-task-to-task efficiency translation in the memory;

measure a total light level using the photo sensor at the non-task location within the architectural space at a second time, wherein the second time is different than the first time;

determine a third ambient light level at the non-task location using the total light level; and

determine a light adjustment value for illuminating the first location from the third ambient light level and the non-task-to-task efficiency translation, wherein determining the light adjustment value is determined from;

L_adjustment=L_{desired at first location}−

KL_{second location},

where L_adjustment is the light adjustment value, L_{desired at first location} is the desired light amount at the first location, K is the non-task-to-task efficiency translation, and L_{second location} is the second ambient light level at the second location.

8. The light sensor according to claim 7, wherein the non-task-to-task ambient translation comprises a table having a plurality of constants.

9. The light sensor according to claim 7, wherein the controller is further configured to determine the light contribution of one or more light fixtures to the light level at the non-task location;

and wherein the third ambient light level is determined from the total light level and the light contribution of the one or more light fixtures.

10. The light sensor according to claim 7, wherein the non-task-to-task ambient translation is the ratio of the first ambient light level at the first location and the second ambient light level at the second location.

11. A method for determining the ambient light level at a task location, the method comprising:

measuring a total light level at a non-task location;

determining an ambient light level at the non-task location from the total light level at the non-task location; and

determining an ambient light level at the task location from the ambient light level at the non-task location, determining a light adjustment value for illuminating the non-task location from the ambient light level at the task location and the non-task-to-task efficiency translation, wherein determining the light adjustment value is determined from;

L_adjustment=L_{desired at first location}−

KL_{second location}, where L_adjustment is the light adjustment value, L_{desired at first location} is the desired light amount at the non-task location, K is the non-task-to-task efficiency translation, and L_{second location} is the ambient light level at the location.

12. The method according to claim 11, wherein the ambient light level at the non-task location is determined using a ratio of a previously measured ambient light level at the task location and a previously measured total light level at the non-task location.

13. A method for determining a light adjustment value for a light source, the method comprising:

measuring a first light level at a task location;

determining a first light delivery efficiency at the task location from the first light level;

measuring a second light level at a non-task location determining a second light delivery efficiency at the non-task location from the second light level at a time near the first time, wherein the task location is different than the non-task location;

determining a non-task-to-task efficiency translation from the first light delivery efficiency and the second light delivery efficiency;

measuring a third light level at the non-task location; and

determining a light adjustment value for illuminating the task location from the third light level and the non-task-to-task efficiency translation, wherein determining the light adjustment value is determined from;

L_adjustment=L_{desired at task}−

KL_non-task,2

where L_adjustment is the light adjustment value, L_{desired at task} is the desired ht amount at the task location, K is the non-task-to-task efficiency translation, and L_non-task is an ambient light level at the non-task location.

14. The method according to claim 13, wherein the non-task-to-task efficiency translation comprises a table having a plurality of constants.

15. The method according to claim 13, further comprising sending the light adjustment value to a light source.

16. A method comprising:

measuring a first total light level at a non-task location;

storing the first total light level in a memory;

measuring a second total light level at the non-task location;

storing the second total light level in the memory; and

in the event the second total light level is different than the first total light level, determining a light adjustment value for a task location from the second total light level, wherein the light adjustment value is determined from;

L_adjustment=−

E_task,2 C−

Δ

L_non-task,2, wherein L_adjustment is the light adjustment value for the task location, E_task,2 is the light delivery efficiency of a light fixture at the task location, C is a non-task-to-task ambient translation, and Δ

L_non-taste,2 is the difference between the first total light level and the second total light level.