Zygo’s Guide to Typical Interferometer Setups

Zygo’s Guide to Typical Interferometer Setups

Core positioning and applicable scenarios

1. Positioning and Value

This manual should be an authoritative reference for the scenario based configuration of Zygo interferometers, with the core goal of helping users:

Clarify the correspondence between "measurement requirements → configuration plan" (such as transmission plane for planar measurement and dedicated optical components for non spherical measurement);

Master the construction process of different configurations (such as optical alignment, mechanical fixation, software debugging);

Avoid configuration errors (such as incompatible accessories, environmental interference causing accuracy deviation), and ensure that the measurement system meets the design specifications.

2. Applicable interferometer host range

Based on the Zygo interferometer product line, the core host models and adaptation scenarios covered in the manual are speculated as follows:

Key Configuration Points for the Core Application Fields of the Interferometer Series

GPI series (such as GPI XP, GPI Pro) large aperture optical components (4-18 inches): flat mirrors, spherical lenses, prism large-sized optical accessories, heavy-duty stages, vibration isolation systems

VeriFire series (such as VeriFire MST, VeriFire Sphere) high-precision wavefront analysis, non spherical measurement: optical lens, laser resonant cavity high-resolution imaging component, non spherical dedicated transmission element, dynamic calibration module

NewView series (such as NewView 5000, NewView 7000) micro morphology measurement: MEMS devices, microstructure surfaces, step height high magnification microscope objectives, white light scanning module, precision Z-axis drive

Speculative core content framework

1. Classification of typical configuration schemes (by measurement object)

The manual is likely divided into chapters based on the type of component being tested, providing targeted configuration cases. Each case includes a component list, technical parameters, construction steps, and accuracy verification. It is speculated that the core solution is as follows:

(1) Measurement configuration of planar components (such as glass plates, flat mirrors)

Core component list:

Host: GPI Pro (8-inch caliber);

Optical accessories: 8-inch transmission plane (TF, flatness ≤ 0.02 λ RMS, λ=632.8nm), laser collimator;

Mechanical accessories: manual fine adjustment stage (X/Y axis accuracy ± 1 μ m), passive isolation stage (isolating 1-10Hz vibration);

Software: MetroPro 9.0 (loads the "Plane Measurement" application module).

Key configuration points:

Optical alignment: The center of the transmission plane is coaxial with the optical axis of the interferometer (deviation ≤ 0.1mm), verified by MetroPro's "center calibration" function;

Environmental control: temperature 20 ± 0.5 ℃ (to avoid material thermal deformation), humidity 40% -60% (to prevent condensation on optical surfaces);

Accuracy index: Flatness measurement repeatability ≤ 0.05nm RMS, measurement range covering 4-8 inch components.

(2) Spherical component measurement configuration (such as convex/concave spherical lenses)

Core component list:

Host: VeriFire MST;

Optical accessories: Transmitting sphere (TS, curvature radius matching the tested object, such as 100mm), polarizer (optimized fringe contrast);

Mechanical components: programmable stage (X/Y/Z axis repeat positioning accuracy ± 0.5 μ m), spherical centering fixture;

Software: MetroPro "Spherical Analysis" module (supports calculation of curvature radius and surface shape error).

Key configuration points:

Selection of Transmitting Spherical Surface: Match the "curvature radius+aperture" of the tested spherical surface (such as selecting the TS-100 model for a 100mm curvature radius lens);

Auto null: Reduce tilt/eccentricity errors in spherical measurements through software calibration;

Accuracy index: curvature radius measurement error ≤ 0.1%, surface shape error repeatability ≤ 0.03 λ RMS.

(3) Microscopic morphology measurement configuration (such as MEMS devices, microstructures)

Core component list:

Host: NewView 7000;

Optical accessories: 50X Mirau objective lens (NA=0.4, working distance 0.3mm), white light scanning module;

Mechanical components: Nano level Z-axis drive (stroke 100 μ m, accuracy ± 0.01 μ m), vacuum suction cup fixture (fixing small components);

Software: MetroPro "roughness analysis" module (supporting Ra, RMS, Rz calculations).

Key configuration points:

Objective calibration: Use Zygo standard calibration parts (such as 1 μ m step height standard parts) to calibrate the lateral resolution (such as 50X objective → 2.5 μ m/pixel);

Scanning parameters: Set the scanning length according to the height of the microstructure (such as selecting a scanning length of 20 μ m for a 10 μ m microstructure);

Accuracy index: The measurement error of step height is ≤ 0.05 μ m, and the repeatability of roughness measurement is ≤ 0.1nm Ra.

(4) Online measurement configuration for production lines (such as automotive glass, consumer electronics lenses)

Core component list:

Host: VeriFire Pro (high stability design);

Optical accessories: fast imaging camera (frame rate ≥ 30fps), dust-proof transmission plane;

Mechanical components: Automated loading and unloading mechanism, production line dedicated vibration isolation platform (isolating 50-200Hz vibrations);

Software: MetroPro "Automatic Measurement Sequence" module (supports real-time data upload to MES system).

Key configuration points:

Beat adaptation: Single piece measurement time ≤ 10s (matching production line speed);

Environmental adaptability: accessory protection level IP54 (dustproof and waterproof), working temperature -10 ℃~40 ℃;

Data output: Supports TCP/IP protocol and is linked with the production line control system.

2. Configure general processes and operating standards

The manual may include "general steps for configuring and setting up", which are applicable to various measurement scenarios. The estimated process is as follows:

Requirement confirmation: Clarify the parameters of the tested part (size, material, accuracy indicators), environmental conditions (laboratory/production line), and efficiency requirements;

Component selection: Match accessories according to the host model (refer to Zygo's "Accessories Host Compatibility Table"). For example, GPI 12 inch hosts require a 12 inch transmission plane;

Mechanical construction:

Fixed host: calibrate the host's levelness with a spirit level (deviation ≤ 0.1 °);

Installation accessories: The transmission element is fixed by adjusting the bracket to ensure that the optical axis is coaxial (deviation ≤ 0.05mm);

Environmental control: Deploy isolation table and temperature control system (if laboratory requires ± 0.1 ℃ constant temperature);

Optical debugging:

Laser alignment: Ensure that the incident laser is parallel to the reference wavefront through a "laser collimator";

Fringe optimization: Adjust the light intensity (through MetroPro's "Light Level" function) to achieve a Fringe contrast ratio of ≥ 80%;

Software configuration:

Loading application: Load the corresponding application module (such as "Sphere. app") for the scene in MetroPro;

Calibration system error: Measure standard components (such as Zygo reference plane), generate system error files (. dat), and enable the "Subtext Sys Err" function;

Accuracy verification: Measure standard parts, compare the "measured value" with the "standard value", and ensure that the deviation is within the allowable range (such as flatness deviation ≤ 0.05 λ).

3. Common configuration issues and solutions

The manual may include a "troubleshooting" chapter, which provides solutions to typical problems in configuration. It is speculated as follows:

Possible causes and solutions for the problem phenomenon

Poor measurement repeatability (deviation>0.1nm RMS), environmental vibration interference, replacement of active isolation table, or adjustment of isolation table parameters (such as increasing damping)

Data missing (no fringe in some areas) Optical accessories contaminated. Clean the transmission plane/spherical surface with a lint free cloth dipped in isopropanol

Incompatible accessories (unable to install). The accessory model does not match the host. Please refer to the "Accessories Host Compatibility Table" in the manual and replace it with the corresponding model (such as GPI XP, select "XP Series Special Transmitting Spherical Surface")

Low measurement efficiency (single item>30s). Upgrade the manual operation of the stage to a programmable stage and enable MetroPro's "automatic measurement sequence"