Can the flashlight adjust its brightness?

The flashlight can adjust the brightness.

The dimming principle of flashlight mainly adopts current adjustment and pulse width modulation. The flashlight has a built-in circuit board, and the brightness of the light can be adjusted by controlling the components on the circuit board. Current adjustment: the flashlight has a built-in voltage stabilizing circuit, which can adjust the current through the LED to change the brightness as needed. By changing the current, the brightness of LED will change accordingly. This adjustment method is relatively simple, but the utilization of battery energy is not efficient enough.

Pulse width modulation (PWM dimming): This dimming method simulates light with different brightness by controlling short interval pulses of current. The dimming circuit will quickly switch the current, so that the brightness of light appears to be constantly changing in people's eyes. By adjusting the pulse frequency and duty ratio (the ratio of pulse high level to total period), the stepless adjustment of light can be realized. Pulse width modulation has the advantages of high energy efficiency and wide dimming range, and is a commonly used dimming method at present.

The birth of flashlight

Modern Wen Mingzhen should thank the American inventor Thomas Edison, who made the first white light with commercial value and brought light to mankind. However, Conrad Hubert deserves the same respect. He immigrated from Russia to the United States 0/00 years ago and invented the flashlight. Hubert came home from work, and a friend proudly showed him a flashing flowerpot. It turned out that he put a battery and a small light bulb in the flowerpot. As soon as the switch was turned on, the light bulb lit up the flowers and looked dazzling.

Hubert was fascinated by it, which inspired him. He sometimes walks in the dark at night, one foot high and one foot low, which is very inconvenient. Not long ago, he had to carry a heavy oil lamp to the dark basement to find something. He believes that if electric lights can be used for portable lighting, it will be impractical and inconvenient. So Hubert put the battery and light bulb in a tube, and the first mobile lighting flashlight came out.

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