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Grove - light sensors and color

Light sensors and color for the Grove system based on fotodiodach or fotorezystorach represent a universal solution for applications in which the key is the detection of light and its intensity. The small size of the modules, easy to run, compatible with Arduino and Raspberry Pi, as well as the ability to work with other modules, external to embedded systems, are the main advantages of a light sensor Grove. Check out our offer of the sensors of light and color, prepared with the needs of Your projects!

How do the light sensors?

Element input, light sensors, often fotorezystor element whose resistance varies with intensity of light falling on its surface. Maximum resistance fotorezystora is a result of the blackouts of the environment of the sensor. Fotorezystory find application in systems of automation control of lighting, as sensors zmierzchowe - when the lighting in the area of the sensor will be weak, then the control system detects an over-voltage threshold circuit with fotorezystorem that the result will be the power for lighting. The measurement light, very well implemented sensors based on photodiodes. When a beam of light is directed toward the photodiode, the free electrons present in the structure of the connectors, the photodiodes will be amazed at the orderly movement or flow of electric current, which power will increase along with the intensity of light received fotodiodę. In the basis of mechanism of action of photodiode work, in particular, solar panels.

Recognition of colors through RGB LEDs

Color is the result of interaction between the object and the light falling on the object from the observer. The light falling on the object is through it is partially reflected and partially absorbed, depending on the optical characteristics of the surface of an object the object, for example in green color, will absorb most of the red and blue colors contained in the spectrum, but the impact towards the environment, most green in color, contained in the same spectrum. For color recognition with the help of electronics, sensors are used based on RGB LEDs. Color recognition and measurements of the content of the component colors is, as a rule, by two methods. The simplest way is to use a light source with adjustable color of light emitted and a sensor measures the intensity of light. Most color sensors used in industrial applications, consists of a white light source and three separate light sensors, each of which emits light at a certain wavelength, respectively: red - 580nm, green 540nm, and blue - 450 nm. The resulting color depends on the intensity of the light emitted by each of the diodes independently of one another. The sensor output is an analog signal voltage, which corresponds to the color that stays jumped to the side of the sensor. This means that, when the analyzed object has a color, such as red with a wavelength of approximately 580nm, it was lights only the red LED module sensitive and similarly for objects, green, and blue. The output signal from the sensor is then passed to the Converter analog to digital in the database. Our offered sensors light Grove, based on fotorezystory or photodiodes are characterized by high sensitivity, wide measuring range and small size, making them perfect for use in the device in which the key factor is the measurement of light intensity and color recognition.