Over the last five years, camera phones have revolutionised the mobile phone market, growing from (barely) nice-to-have features, to key must-have features. More than half of all mobile phones sold in 2006 came with an embedded camera, and camera phone sales could hit the 1 billion mark by 2010.
Making the most of this success, handset manufacturers are now looking at grabbing an even bigger market by taking the low end digital still camera market. For this they need to deliver the same level of image quality.
The first step is to increase pixel count. The current market trend is clearly showing an increase in resolution with mobile phone manufacturers pushing ‘‘mega-pixels’’, with many 2 or 3MP camera phones being launched today.
Sensor sizes are at the same time being reduced to fit trendy slim phones, hence smaller pixels are constantly being developed (from 5.6μm 3 years ago, to 2.8μm last year, and even 2.2μm this year). But this comes at the expense of sensor sensitivity.
The next challenge is to add better optics. Features such as auto focus, zoom lenses, and anti-jitter mechanisms, which are standard features on today’s digital still cameras.
The need for auto focus is also driven by the emergence of new mobile applications, ranging from bar code scanning to biometrics and optical character recognition. These applications especially require greater auto focus accuracy, sharper and crisper focus, and fast response times.
However, where makers of digital still cameras can easily add more circuitry and/or rely on expensive mechanical systems for auto focus and zoom, camera phone boards are tightly packed, requiring small and extremely reliable components.
Therefore camera modules manufacturers are faced with the challenge to develop small, reliable and inexpensive auto focus solutions to meet the demand from handset manufacturers.
Varioptic’s liquid lens auto focus solutions feature some crucial advantages over traditional technologies in terms of robustness, cost, size, ease of integration, power consumption and speed Varioptic has developed several products to meet the demand from the camera phone market.