How to Remove the Annoying Camera Bump from Smartphones

The bump is not just aesthetically displeasing, but also gives rise to practical issues – for instance when the handset is on a flat surface, such as a desk or table, this causes the phone to rock as you touch the screen to type or navigate, causing errors and irritation.

So why is there a bump in the first place? It arises from the competing consumer demand for slim handsets on the one hand and improved camera quality on the other. In order to deliver upgraded camera specifications, larger components are necessary such as image sensors with more megapixels, lenses with larger apertures and lens actuators with greater driving power and axes of motion.

At CML we recognise that the camera bump is a key issue for smartphone designers in this highly competitive market. So CML has leveraged its shape memory alloy (SMA) platform technology to address this industry issue.

The camera bump arises from two factors – firstly, the thickness of the actuator that moves the lens to keep the image in focus and remove blur caused by handshake, and secondly the height of the lens that guides the light accurately onto the image sensor.

For the first issue, SMA actuators are more than one millimetre thinner than those using the incumbent voice coil motor (VCM) technology.

If SMA addresses the camera bump being caused by the first issue of the actuator, then the lens thickness may still cause a bump as the next weakest link in the chain. Currently smartphone camera lenses are made from plastic. In contrast, professional handheld camera lenses are made from glass, as it is a higher quality and more powerful material to guide light. Glass lenses are being developed by smartphone lens companies to provide improved performance and in parallel reduce the thickness of the lens.

A complication of using glass lenses is that they are much heavier than their plastic equivalent. The incumbent VCM actuators are lower force than CML’s SMA actuators and the additional weight of glass lenses compromises the performance of VCM actuators, to the point where there is an overall reduction in camera performance and functionality. CML have demonstrated that our SMA actuators can move glass lenses without any impact on actuator performance.

CML’s manufacturing partners have already shipped SMA actuators in mass production under licence from us for numerous devices, addressing other major industry issues such as mechanical impact resistance and power consumption. We are currently working on projects to deliver market-leading miniaturisation to remove the camera bump (for good) and look forward to sharing the details shortly when these products are available in the open market.