This effect, known as diffraction, makes it hard to keep audio ... Pennsylvania and Lawrence Livermore National Laboratory used ultrasound and nonlinear acoustics to "bend" soundwaves to produce ...

The emergence of imaging schemes capable of overcoming Abbe's diffraction barrier is revolutionizing optical microscopy. In 1873, the German physicist Ernst Abbe realized that the resolution of ...

Ultrasound close ultrasoundSound with a frequency greater than 20,000 Hz (20 kHz). waves have a frequency higher than the upper limit for human hearing – above 20,000 Hertz (Hz). Different ...

Ultrasound close ultrasoundSound with a frequency greater than 20,000 Hz (20 kHz). is sound with a frequency greater than 20,000 Hz. Humans cannot hear ultrasound but many other animals can, such ...