View source for LUX1000 User Guide

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<metadesc>The Light Phidget measures the ambient light level from 188 μlux to 220 klux and connects to a port on your VINT Hub.</metadesc>
[[Category:UserGuide]]
==Part 1: Setup==
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== Part 2: Using Your Phidget ==

===About===
The LUX1000 measures brightness (illuminance) from 188 microlux (starlight on a moonless night) to 220,000 lux (direct sunlight).

[[Image:LUX1000-about.jpg|850px|link=]]

===Explore Your Phidget Channels Using the Control Panel===

You can use your Control Panel to explore your Phidget's channels.

'''1.''' Open your Control Panel, and you will find the '''Light Phidget''' channel:

[[Image:LUX1000_Panel.jpg|link=|center]]

'''2.''' Double click on the channel to open an example program. This channel belongs to the '''Light Sensor''' channel class:
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{{UGC-Entry|Light Phidget: |Measures the illuminance in the area the LUX1000 is facing
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In your Control Panel, double click on "Light Phidget":
[[Image:LUX1000-LightSensor.jpg|center|link=]]}}

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== Part 4: Advanced Topics and Troubleshooting ==

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{{UGC-Entry|Dynamic Gain and Sampling|
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[[Image:LUX1000_response.jpg|link=|375px|thumb|The response of the photodiodes depending on the wavelength of the incoming light.]]
The LUX1000 can measure the intensity of light in the range of 188µlx to 220klx. The device achieves this wide range due to its ability to dynamically change the gain value on its measurements, in addition to changing the amount of integration time taken per measurement. Changing the gain coarsely affects the range, while changing the integration time finely affects the range.

Because of these dynamic ranges, you may see momentary saturation when trying to measure large changes in light intensity in short periods of time (for example, a strobe light). Once the light level stabilizes, the sensor will settle back into optimal range settings.}}
{{UGC-Entry|Spectral Response|
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The light sensor on the LUX1000 is designed to sense light in a way that emulates the response of the human eye. However, digital light sensors work very differently than our eyes do. Using the photoelectric effect, the photodiodes in the sensor will generate current when struck by incoming photons. The problem is that the range of wavelengths that these photodiodes respond to vary depending on what materials they are made of, and none of them have the same response as the human eye.

The solution, offered by the chip used in the LUX1000, is to take readings from two different photodiodes. One photodiode detects only IR light (light invisible to the human eye), and one photodiode detects both visible and IR light. The device weights the measurements with coefficients based on calibration testing. Then takes the difference between the IR component from the combined IR and visible light. The result is a workable approximation of brightness, as seen by a human eye.}}


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