Scanning acoustic microscopy is a non-destructive imaging technique that uses sound waves to investigate the internal features of opaque materials. In SAM, imaging is performed using a focused ultrasonic beam for imaging analogous to an optical microscope. 

Acoustic microscopy techniques analyze the intensity and phase of both the reflected and transmitted waves to create visual images reflecting the variations in the acoustic impedance of the specimen, thereby disclosing internal flaws and defects such as delamination and voids. 

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The operational principle of SAM is that a transducer is affixed to an acoustic lens. This lens, in turn, is linked to the object through liquid (distilled water). The acoustic lens often features a sapphire delay line: its transducer-side is flat, while the opposite end boasts a spherical curvature. This design enables the ultrasonic waves generated by the transducer to be focused, leveraging the significant difference in sound velocity between the coupling medium and the delay line to achieve this effect.

The method assesses the echoes produced by the contrast in acoustic impedance (Z) between different materials. Acoustic impedance is calculated using the formula Z = ρ x c, where ρ represents the density of the medium and c denotes the speed of sound within that medium.

​A crucial factor in conducting effective acoustic inspections is the choice of the transducer or probe frequency, as it directly affects the resolution of the image obtained. Additionally, the depth to which the acoustic waves can penetrate the material under examination is influenced by the frequency of the transducer. Thus, selecting the appropriate frequency for inspection is essential and should be based on the specific properties of the material, the thickness of the specimen, the depth of the features of interest, and the desired resolution. Higher frequencies lead to enhanced resolution but reduce the penetration depth of the acoustic waves. Conversely, lower frequencies allow for greater penetration depth but at the cost of resolution. Frequencies in the range of 200 MHz to 400 MHz are typically utilized for transducer frequencies in various applications.

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In scanning acoustic microscopy, the unique contrast observed in images is a result of the elastic interaction between high-frequency acoustic waves and the target material. The core process involves generating and focusing high-frequency acoustic waves, specifically longitudinal or compressional waves, to a target. Subsequently, the echoes of these waves are detected. Both the amplitude and timing of these echo pulses enable the mapping of the local mechanical or elastic properties of the sample. This technique achieves a spatial resolution of up to 1 µm, allowing for detailed visualization of the specimen's characteristics.

Our digitizers come equipped with a range of features that make them an ideal choice for integration into scanning acoustic microscopy systems, providing advanced capabilities to enhance imaging and data processing.

• Open FPGA (Xilinx): We offer an open FPGA (Field-Programmable Gate Array) platform based on Xilinx technology, allowing for the integration of customer-specific firmware alongside our standard or customized firmware. This flexibility ensures that the digitizer can be tailored to meet the unique requirements of each SAM system.
• Customized Firmware Packages: Our digitizers can be enhanced with customized firm  ware packages, including an Advanced Time Domain firmware (FWATD), which supports filtering and averaging to boost the dynamic range. This capability is crucial for achieving the high precision required in SAM applications.
• P2P (Peer-to-Peer) Streaming: The digitizers enable high-speed data streaming directly to a GPU (Graphics Processing Unit) or disk, facilitating real-time data processing. With support for 8-bit compression, data can be streamed at speeds up to 14Gbytes/s, making it possible to handle large volumes of data efficiently.
• Real-Time Data Streaming and Computational Capability: Our devices can support real-time data streaming, enabling huge computational capabilities. For instance, they can achieve 16,000 floating-point operations per sample at a sampling rate of 5GSPS (Giga-Samples Per Second) in real time. This exceptional performance is key for applications requiring high-resolution 3D imaging and very fast defect detection in real time.

These features combine to offer a powerful and versatile solution for scanning acoustic microscopy systems, ensuring high-speed, high-resolution imaging capabilities and real-time data processing, essential for advanced diagnostics and research applications.​