IPL Lamp Current Modulation for Smoother Hair Treatment Pulses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hair removal devices using Intense Pulsed Light (IPL) technology cause user discomfort due to a high initial light output peak, which is painful and unpleasant, and current solutions for mitigating this discomfort are either costly or require significant space, making them impractical for home-use devices.
Innovation Solution
A hair treatment device with an IPL lamp driven by a drive circuit that includes a switch modulated at frequencies between 50 kHz to 500 kHz to provide pulsed current delivery, reducing the initial current peak and associated light output peak without additional inductive or capacitive components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a high voltage is applied to generate electrical breakdown of gas inside the lamp, then the plasma channel is formed, but the initial current peak causes high light output intensity that creates user discomfort
Solution Approach 1:
The patent applies periodic action by switching the current delivery in pulses at a frequency of 50 kHz to 300 kHz. The switch is controlled to deliver current in pulses with a duty cycle of 10% to 50%, creating periodic on-off cycles that smooth the light output intensity and eliminate the initial peak that causes user discomfort, while still enabling reliable plasma channel formation.
2Object-affected harmful factors
If additional inductive or capacitive components are added to smooth the current peak, then user discomfort is reduced, but device complexity, size and cost increase
Solution Approach 1:
The patent extracts the current smoothing function from traditional inductive or capacitive components and implements it directly through the switch control mechanism. By controlling the switch timing and duty cycle, the system achieves current peak reduction without requiring additional reactive components, thereby reducing device complexity while maintaining user comfort.
Solution Approach 2:
The switch control system performs self-regulation of the current delivery profile without requiring external reactive components. The controller automatically adjusts the pulse timing and duty cycle to smooth the current peak, making the system self-sufficient and eliminating the need for additional complexity-prone components like inductors or capacitors.
3Illumination intensity
If the switch is controlled at high frequency to smooth the current peak, then light intensity profile is improved, but switching losses and thermal load increase
Solution Approach 1:
The patent optimizes the switching frequency parameter within the range of 50 kHz to 300 kHz and controls the duty cycle between 10% to 50%. By carefully selecting these parameters, the system achieves sufficient light intensity smoothing to eliminate user discomfort while keeping switching losses and thermal load within acceptable limits for continuous operation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces user discomfort by smoothing the light intensity profile over the IPL pulse duration, maintaining comfort while optimizing treatment efficiency and reducing device size and cost.
Implementation Method 1
an intense pulsed light, IPL, lamp; a drive circuit for driving the IPL lamp with pulses of energy
Implementation Method 2
Photo-epilation is well known for hair removal and hair growth reduction. The light absorbed by melanin in the hair and hair matrix generates heat that damages the hair follicles.
Implementation Method 3
a switch in series with the IPL lamp; and a controller for controlling the switch at a frequency in the range 50 kHz to 300 kHz thereby to provide pulsed delivery of current to the IPL lamp
Implementation Method 4
The plasma ignition unit 10 generates a conductive plasma channel of ionized gas atoms or molecules between the lamp electrodes (inside the lamp tube). At first, a high voltage (of around 15kV) is applied between the lamp electrodes. The high voltage is needed to generate the electrical breakdown of the gas inside the lamp.
Implementation Method 5
Energy is stored in a main storage capacitor 12 (e.g. 100J of energy at 400V). The electrical energy stored in the capacitor is discharged through the lamp 14, resulting in a pulsed operation of the lamp.
Implementation Method 6
The electrical energy stored in the capacitor is discharged through the lamp 14, resulting in a pulsed operation of the lamp.
Data Source
Figure 1a~1b
Figure 2a~2b
Figure 3~4
AI summary
A hair treatment device comprises an IPL lamp driven with pulses of energy. A switch is in series with the IPL lamp and is switched at a frequency in the range 50 kHz to 500 kHz to provide pulsed delivery of current to the IPL lamp with pulses shorter than the overall IPL pulse duration The current modulation is used to eliminate the initial current peak and its associated peak in light output. The modulation can be used during the entire IPL pulse, or only during a fraction of it, while the duty cycle or the frequency of the modulation can change during the IPL pulse in order to optimize the light output. A pulsed delivery of current is provided to the IPL lamp during a first portion of the pulses of energy and a continuous delivery of current is provided during a last portion of the pulses of energy.