Photoacoustic Imaging with Multiple-Wavelength Light-Emitting Diodes

Abstract

Multiple-color light-emitting diodes (LEDs) were used for photoacoustic (PA) imaging of printed color specimens, and the obtained PA images agreed well with the corresponding amount of absorbance of the specimens. The LED light sources with wavelengths of 455, 505, 617, and 660 nm were used to evaluate PA images that were obtained for colored specimens printed on the front and rear surfaces of an OHP sheet. The PA images obtained for individual wavelengths were combined to recover the colored image of the specimen, and the recovered image was compared with the original full-color image. The PA signals with amplitudes and phases behave as vectors so that the vectorial addition of PA signals generated from the surface and undersurface well describes the PA signal behavior. Furthermore, imaging of a layered specimen with a surface color layer was also carried out, which lead to successful thermal depth profiling with a colored optical source.

Multiscale Functional and Molecular Photoacoustic Tomography

“…The most expensive components in PAT are typically the pulsed laser source and the ultrasonic transducer array. Several groups have explored inexpensive light sources [183, 201–205]. For example, Li et al have developed an OR-PAM system using a low-cost Blue-ray DVD pickup head with a 405 nm laser diode [205].…”

On the Pollen Detection with Photoacoustic Imaging

“…The basic experimental setup of a PAM is similar to the previous publicatios [7,8] and shown in Figure 2. The apparatus is basically adopted gas-microphone (Brewer & Kaejer 4166) detection and linear-motor stage (Chuo Seiki, ALD-105-H1L) driving system.…”

“…To reduce interfering PA noise that might be generated by other particles, differential absorption PA method [7,8] is favorable. Author's group is developing a multi-pleco-lor LED and LD PA imaging system.…”

Use of a single xenon flash lamp for photoacoustic computed tomography of multiple-centimeter-thick biological tissue ex vivo and a whole mouse body in vivo

“…Clearly, a costeffective and compact alternative illumination source would benefit certain applications. To this end, researchers have investigated pulsed laser diodes (LDs), [6][7][8][9] light-emitting diodes (LEDs), 10,11 and xenon flash lamps. 12 Using pulsed LDs, Upputuri and Pramanik 9 have imaged a blood-filled tube in chicken breast tissue up to 2-cm deep.…”

“…However, pulsed LDs are typically available only at wavelengths greater than 800 nm, which limits the choices of label-free absorption-based contrasts. Using LEDs, Adachi and Hoshimiya 10 have successfully imaged printed characters. However, modulated LEDs have a long pulse width, which limits the bandwidth of the acoustic signals.…”