Mood lamps are always fascinating for me and is a very good project for starters to start with Arduino.
What is a Mood Lamp ?
Mood lamps are lighting devices that are used to establish a particular feeling or mood within a room. In some cases, this type of lamp may be a small device that is plugged into an outlet and creates points of light near the floor line of the room. Other examples of a mood lamp may be used to illuminate specific points along the walls or cast a soft light over a larger piece of furniture in the room.
Mood lighting differ somewhat from other lamps in that their purpose is not so much practical as aesthetic. Reading lamps for example tend to provide bright light to a given space in order to make it possible to read a book or magazine without creating strain on the eyes. Overhead lighting is used when there is a need to illuminate the majority of the space, such as in a classroom or laboratory. By contrast, a mood lamp is used to help create a specific ambiance within the room as a means of making the space more attractive and welcoming in some manner.
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Step 1: Components
The component list way too small but there are diversity in the list . i actually reviewed three types over the this instructables
anyways the list .
Arduino
RBG led
HC-05
Jumpers
Bread Board
Comparison of all the variants
RGB led : Easily available in ebay and all radio shack or locals store.
High Color Output. Can be easily power withi arduino .
RGB SMD : This are sold as module i test a common cathode version the seem not to wrk great with arduinos internal power supply.
RGB LED Strip : These are the Best comes with highes color range output with a correct driver you can drive them to give insane level of colors.
Indians can find these at this link
you will also need this app to control it with bluetooth
Step 2: What Is RGB Led ?
Normal led emits monochromatic color output which may be red ,green, or blue.To obtain other color we need to combine the color RGB . This result in 7 different color.To produce more than 7 colors, each color channel should be able to change in brightness, not just turned on or off.
A popular control method is PWM, of which the cycle duty range determines the available brightness levels. The more the levels are available, the more colors can be produced. Apart from the popularity in applications like outdoor decoration lighting in cities, stage lighting designs, home decoration lighting and LED display matrix, RGB color mixing technology can also be found recently in LCD backlighting and projectors.
We learn about PWM later in this Instructables.
RGB can be be of two type
Common Cathode or Common Anode
Common Cathode Three led channel has a single Cathode
Common Anode Three led channel has a single Anode
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