The CONEX-LDS autocollimator performs high-resolution, non-cotact angular measurements for alignment, quality assurance and metrology applications. The controller is integrated in the body of the autocollimator making it ideal for systems integration or as a portable metrology tool. The CONEX-LDS is used in the highest precision applications performing high resolution angular measurements at over distances of up to 5 meters.
The resolution of the CONEX-LDS is actually 0.003 µrad. Including the sensor noise, the sensitvity stays at 0.01 µrad, which is a very excellent value for angular measurement.
The CONEX controller works in junction with the internal position sensor detector to provide high speed data acquisition rates up to 2 kHz. This feature is ideal for vibration measurements, structural drift, or even metrology applications like wobble measurements of bearings.
Newport's CONEX-LDS supplies an intuitive, built-in alignment window used for coarse alignment of the optics. This allows the user to manually and quickly setup the autocollimator.
For out-of-the box control, the CONEX controller is preconfigured and delivered with the sensor. To start using the CONEX-LDS, the device simply requires plugging in the power supply, connecting the USB communication, and starting the free GUI. Once the GUI has been started, the layout is intuitive and straightforward. From the front panel, the user can access graphical displays of gathered data.
A calibration report is provided with each individual unit, certifying its performance. CONEX-LDS-VER is available to easily verify the unit's calibration on a regular basis. If the unit is out of calibration, it can be returned to the factory for re-calibration.
A very compact controller is integrated into the autocollimator head of the CONEX-LDS. This allows for easy setup, smaller footprint, lightweight design, and easy connections directly to the PC and power.
The CONEX-LDS comes with a CONEX-LDS-CABLE5 only. The CONEX-PS and CONEX-USB-RS422 must be ordered separately.
This is a classical application for autocollimators. To obtain flatness measurements, the autocollimator beam is reflected off a mirror. By indexing the mirror along the beam path at known distances, linear position vs. the pitch angle is obtained and is used to determine vertical displacement.
In manufacturing environments or metrology applications that utilize dividing heads or rotation stages with mechanical or air bearings, the CONEX-LDS is a very useful tool to verify the wobble of the bearings. In the manufacture of ball, thrust or air bearings, particularly those with large diameters, in-process or final verification of wobble specifications can be accomplished with the CONEX-LDS. In both cases, a simple mirror mounted perpendicular to the rotation axis with the CONEX-LDS beam coincident to it, will provide high precision measurements of wobble that will characterize the condition of the bearing. The results could indicate the need for maintenance, repair or rework. The graph on the right illustrates a typical result of a wobble test of a bearing. Using the same CONEX-LDS setup, but with a precision ball fixture rather than a mirror, it is possible to determine the axial eccentricity of a bearing.
Pitch and Yaw deviations during motion increase positioning errors due to the Abbe effect, especially at a longer distance between the sample and the feedback encoder. With the CONEX-LDS autocollimator, this type of error can be accurately identified and used to calculate true position. Pitch and yaw can be measured concurrently using a simple flat mirror. In addition, these angular measurements can be used to derive the flatness and straightness deviations of the linear bearing.
The time required for settling into a position is an important parameter in high-accuracy, highthroughput applications like semiconductor inspection. Fast settling times result in processes to be performed very quickly, thus increasing productivity. In this case the CONEX-LDS autocollimator is used to measure the angular displacement at all stage positions, according to the control parameters. The dynamic measurements reflect the stage performance at the given situation. Using Fourier analysis of the same data enables understanding of the stage's resonances.
Rotation stage accuracy can be measured using a precisely calibrated multifaceted mirror. The CONEX-LDS autocollimator measures the angular difference between the stage rotation and index of the calibrated standard. Absolute accuracy is measured directly, taking the index error and hysteresis into account. The measurement accuracy is better than 1 µrad.