WDI’s ATF7 Sensorproject their focusing laser directly through the objective lens of the microscope. This “Through The Lens” （TTL） technique allows the ATF7 to provide extremely accurate autofocus,

The ATF7
WDI’s ATF7 is a high speed, high accuracy, autonomous digital autofocus sensor. Its “Smart Sensor Architecture” (SSA) incorporates a semiconductor laser, built-in CMOS image sensor, FPGA and microprocessor for fast digital image processing. By projecting a laser line onto the sample and digitally processing the image, the ATF7 provides fast and
accurate measurements of the distance and direction to focus. This information can then be output directly to WDI’s MCM+ or MCZ controller, or to any compatible controller.
High Accuracy At Fast Speeds.
WDI’s ATF7 Sensor project their focusing laser directly through the objective lens of the microscope. This “Through The Lens” (TTL) technique allows the ATF7 to provide extremely accurate autofocus, with a success rate typically higher than 99%. The ATF7’s on-board digital processing allows it to couple this accuracy with extremely high speeds.
Static or Dynamic Autofocus
The ATF6 is continually assessing distance and direction to focus, updating its data every 0.6 milliseconds. This allows the sensor to keep samples in focus regardless of whether they are stationary or in motion. This powerful tracking autofocus makes the ATF7 perfect for scanning very large specimens quickly and precisely.
Maximum Flexibility
By projecting a laser line, the AFT7 sensor operates equally effectively on patterned and unpatterned specimens as well as diffusing and reflective surfaces making it ideal for media such as TFT arrays and photo masks. The ATF7 also automatically adjusts its laser intensity and sensor expose time, allowing it to adapt from low reflectivity (down to 1%) to highly reflective
(99%) surfaces. It is compatible with objectives from 2X to 100X, and wavelengths including UV, NUV and NIR. The ATF7 can also achieve focusing with a programmable Z offset function.
ATF7 SensorEasy Integration
All of the sensors in WDI’s ATF family are designed with ease of integration in mind. The ATF7 can be purchased as a
stand-alone sensor with analog output, or as full autofocus systems, integrated with either WDI’s MCM+ controller for
driving an external Z stage or MCZ controller which includes the ability to drive a two-phase stepper motor for Z actuation.
All WDI’s ATF sensors have small, standardized footprints and connections, and can output in either analog or digital
formats, making them both easy to install and easy to upgrade as application requirements evolve. The ATF7 is pin to
pin compatible with the ATF4SA and is thus a “plug and play” upgrade.
 

ATF7 AUTO FOCUS & TRACKING SYSTEM