Sapphire Pendulum Plate | Prosun Semiconductor

As the core sensing element of a flexure accelerometer, the sapphire pendulum plate is connected to the outer frame via an ultra-thin hinge (thickness ≤0.03 mm), forming a freely oscillating cantilever structure. The gold-plated layers on both sides of the pendulum plate serve as the movable electrodes of a differential capacitor, while the fixed capacitor electrodes (e.g., yoke iron end faces) act as the stator plates, forming a capacitive sensor. Under acceleration, the pendulum plate deflects, causing a capacitance change. The servo loop then generates a feedback torque to balance the inertial torque, achieving closed-loop control.

Compared to quartz accelerometers:
Enhanced Precision: The sapphire pendulum plate offers superior long-term stability over quartz, eliminating frequent recalibration, with significantly improved EMI resistance.

Structural Optimization: The sapphire accelerometer features a more compact internal layout, reducing assembly errors through bonding/welding techniques for better mechanical-performance integration.

Model/Specification: (Φ22.2mm)

Sapphire Pendulum Plate

Performance Specifications for IR Wafers:

Technical Parameters

No.	Product Parameters	Technical Indicators
1	Material	Al2O3Industrial Grade
2	Crystal Structure	Hexagonal Crystal System
3	Single Crystal Purity	≧99.999%
4	Diameter	Φ22.2~22.226mm
5	Thickness	0.76±0.02mm
6	Flatness	≤5um
7	Parallelism	≤0.002mm
8	Surface Roughness	≤0.05um
9	Beam Thickness	0.020～0.03mm
10	Beam Width	≧2.8mm
11	Specific Stiffness	7~12g/rad
12	Sag/Deflection	2.6～2.9mm
13	Symmetry	≤0.2mm

Performance Specifications

Material Properties:

Hardness:
Sapphire (Al₂O₃) achieves Mohs 9 hardness (second only to diamond), with far superior wear resistance compared to quartz, making it ideal for high mechanical stress applications.

Thermal Stability:
Melting point up to 2045°C, with an ultra-low thermal expansion coefficient (~5×10⁻⁶/K), ensuring stability across a broad temperature range (-50°C to 200°C).

Chemical Inertness:
Resistant to acids, alkalis, and salt spray corrosion, suitable for harsh environments.

Optical Performance:
Excellent transmittance (190nm–5.5μm), covering UV to mid-infrared wavelengths, ideal for optical windows and laser components.

Refractive index:
1.76–1.77; slight birefringence requires control via crystal orientation (e.g., "zero-degree" cut).

Widely used in aerospace, nuclear industry, medical imaging, industrial radiography, and related fields.

Application Fields

끸

Submit

1. Inertial Navigation & Guidance Systems

Spacecraft & missile navigation
UAV & aircraft control

2. Industrial Monitoring & Precision Machinery
Structural health monitoring (bridges, buildings)
Condition monitoring of precision machining equipment

3. Geological Exploration & Extreme Environment Detection
Geothermal & oil exploration
Mine & tunnel safety monitoring

4. Military & Defense Equipment
Guided munitions & armored vehicles
Underwater vehicle navigation

5. Scientific Research & Microgravity Studies
Microgravity environment experiments
Low-frequency vibration calibration

6. Emerging Technology Integration
Autonomous driving & smart transportation
Medical device dynamic monitoring