Dynamic precision actuators for smartphone cameras
reduce product inspection errors by 10%
Increased demand for camera module precision actuators is being driven by high camera performance & slimmer profiles.
There’s a battle going inside the smartphone. The battle for space. The ever-growing need for slim designs, new functionality, larger memory, and longer battery life means that manufacturers constantly battle to reduce the size of their components.
With camera modules, this is no different. The demand for an increased number of pixels has led to decreased pixel size, for example. This seems logical – but that decreased pixel size has a knock-on effect. Since smaller pixels lead to less light getting in per-pixel, manufacturers need to increase the optical aperture of the lenses to allow for more light to enter the sensor. This adds more size and weight to the camera module that needs to be reduced, and consequently the manufacturing process becomes more complex.
Added to this, smartphone manufactures are diversifying their camera functionality offering in order to win market share. Wide angle lenses, telephoto zoom, 3D cameras, retina sensor and more have all led to the camera becoming an incredibly complex, high tech and varied instrument inside the smartphone.
Consequently, the demand for thin precision actuators to move and position the lens dynamically has increased dramatically. The CAGR between 2020 and 2024 is likely to be 8% for camera modules, 9% for actuators, 13% for OIS compared to just 3% for smartphones in general indicating a trend towards much more complex camera technology and the need to find manufacturing solutions for it. The focus for manufacturers will be to ensure the quality requirements for these complex products are adhered to, and wastage on the production floor will need to be managed carefully.
Dynamic Sensing Technology
One of the big issues when measuring the performance of actuators is that the height, angle and position of the actuators is often measure by separate devices. Any deviation, or loss of correlation between these machines will not produce products to the stringent quality requirements and errors will become an issue.
Where Suruga Seiki have long had the advantage in this industry is the long-standing use of the 5-axis displacement measuring technology that operates at high speed with ease. Complex optical system technology and low-noise, high-speed correction electronics allow the system to dynamically and accurately capture changes in attitude during actuator operation.
This laser sensing technology is capable of simultaneously capturing minute displacements in 5 axial directions (XY position, Z height and TxTy angle). The system provides high linearity measurement results over the full range of measurement with an automatic calibration system developed in conjunction with the complex optical system. High correlation can be obtained even with multiple sensors.
The system instantly corrects the nonlinearity of PSD detection analysis, which is a problem with the displaced sampling rate. Hardware electronics are used for the parts that are critical to the speed of analysis, and this allows for low-noise analog signals to be output at 200 kHz in real time with minimal response delay.
We have succeeded in realizing a fully automated inspection system that is compatible with mass production lines.
Simultaneous measurement of 5-axis displacement (less than 0.4% difference between machines, reducing the error of judging the quality of the actuator caused by measurement uncertainty by more than 10%)
Space-saving and high-volume testing is possible (74.7% less than conventional models)
Quick turnaround for mass production and model change (55% reduction from conventional models)
San Jose, California, USA