The paper by Kuiper and Hendriks (2004) introduces a variable-focus liquid lens for miniature cameras. The lens is based on the meniscus between two immiscible liquids, which can be controlled to change its curvature through electrowetting. This method allows for adjustable focal length without the need for moving parts, making it suitable for miniaturization. The authors demonstrate that a self-centered lens with high optical quality can be formed using two liquids in a tube. They study the lens's performance during focusing actions and design a miniature achromatic camera module based on this adjustable lens. The module is shown to be excellent for portable applications, such as camera phones, due to its robustness, size, speed, power consumption, and durability. The lens's dioptric power can be controlled between -100 and +50 diopters, significantly wider than the range of human eyes. The paper also discusses the environmental conditions and temperature dependence of the lens, as well as the focus speed and chromatic aberration correction. The authors conclude that liquid-based variable lenses offer significant advantages in various optical applications.The paper by Kuiper and Hendriks (2004) introduces a variable-focus liquid lens for miniature cameras. The lens is based on the meniscus between two immiscible liquids, which can be controlled to change its curvature through electrowetting. This method allows for adjustable focal length without the need for moving parts, making it suitable for miniaturization. The authors demonstrate that a self-centered lens with high optical quality can be formed using two liquids in a tube. They study the lens's performance during focusing actions and design a miniature achromatic camera module based on this adjustable lens. The module is shown to be excellent for portable applications, such as camera phones, due to its robustness, size, speed, power consumption, and durability. The lens's dioptric power can be controlled between -100 and +50 diopters, significantly wider than the range of human eyes. The paper also discusses the environmental conditions and temperature dependence of the lens, as well as the focus speed and chromatic aberration correction. The authors conclude that liquid-based variable lenses offer significant advantages in various optical applications.