LIGHT SENSING DEVICE FOR SENSING AMBIENT LIGHT INTENSITY

• US 20150300875A1
• Filed: 11/26/2013
• Published: 10/22/2015
• Est. Priority Date: 12/20/2012
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: MAASS, Henning, MSCH, Guido Josef
• Granted Patent: US 9,797,768 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2560/0242 adapted to measure environmental factors, e.g. temperature, pollution
• CPC Class Codes: A61B 2560/0475 Special features of memory means, e.g. removable memory cards
• CPC Class Codes: A61B 5/165 Evaluating the state of mind, e.g. depression, anxiety
• CPC Class Codes: A61B 5/4857 Indicating the phase of biorhythm clocks or watches with indicators for biological cycles G04B19/264
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: G01J 1/0228 Control of working procedures; Failure detection; Spectral bandwidth calculation
• CPC Class Codes: G01J 1/0233 Handheld
• CPC Class Codes: G01J 1/4204 with determination of ambient light solar light G01J2001/4266
• CPC Class Codes: G01J 2001/0257 portable

Abstract

The invention relates to a light sensing device for sensing ambient light intensity, comprising at least one ambient light sensor and an occlusion detector for detecting an object occluding the ambient light sensor. The invention is further related to a corresponding method for sensing ambient light intensity.

Claims

1. Light sensing device for sensing ambient light intensity,

comprising:

at least one ambient light sensor;

an occlusion detector for detecting an object occluding the ambient light sensor; and

a recording device configured to record one or more parameters of ambient light as a function of time.

2. Light sensing device according to claim 1,

wherein the occlusion detector comprises an infrared sensor and an infrared light source.

3. Light sensing device according to claim 2,

comprising a casing on which the infrared sensor, the infrared light source and the ambient light sensor are positioned on the same side.

4. Light sensing device according to claim 1,

wherein the light sensing device is a wrist-wearable device comprising a wristband.

5. Light sensing device according to claim 1,

further comprising an indicator device for generating an audible, visual and/or haptically perceivable notification signal in case of the detection of an object by the occlusion detector.

6. Light sensing device according to claim 1,

further comprising a processor for processing signals generated by the ambient light sensor and for controlling the occlusion detector

and a memory for storing ambient light values representing the ambient light intensity measured by the ambient light sensor and an occlusion status information representing an occlusion status of the ambient light sensor.

7. Light sensing device according to claim 6,

wherein the processor is provided to activate the occlusion detector only in case the ambient light intensity measured by the ambient light sensor is below a predetermined threshold.

8. Method for sensing ambient light intensity by means of a light sensing device comprising at least one ambient light sensor an occlusion detector for detecting an object occluding the ambient light sensor and a recording device, comprising the following steps:

performing an ambient light measurement with the ambient light sensor,

performing an occlusion measurement with the occlusion detector to determine if the ambient light sensor is occluded by the object, and

recording, with the recording device, parameters that indicate presence or absence of the occlusion.

9. Method according to claim 8,

wherein the ambient light measurement is performed within temporally limited subsequent epochs.

10. Method according to claim 9,

wherein an occlusion measurement is performed for each epoch.

11. Method according to claim 9,

wherein an occlusion measurement is performed only for epochs in which the ambient light intensity is below a predetermined threshold.

12. Method according to claim 9,

wherein an occlusion measurement is performed only for the first epoch in which the ambient light intensity is below a predetermined threshold.

13. Method according to claim 9,

wherein an occlusion measurement is performed for the first epoch in which the ambient light intensity is below a predetermined threshold and repeated periodically as long as the ambient light intensity stays below this threshold.

14. Method according to claim 9,

wherein an occlusion measurement is performed once or periodically repeated after the ambient light intensity has stayed below a predetermined threshold for a predetermined number of epochs.

15. Method according to claim 9,

wherein the predetermined threshold of ambient light intensity and/or a repetition period of occlusion measurements are adjustable by a user.