Redzamās skaņas – mākslinieciski pētījumi fotoakustikā
Authors:   Liepājas Universitāte, Vītola Paula 
Published: June 2023

Since 2015, the author of the article has been researching the photoacoustic effect in her artistic work, experimenting, and developing various prototypes and artworks that allow visitors to experience the effect and understand some of its principles. The photoacoustic effect is a process where sound is generated, recorded, or transmitted using photosensitive material. The article describes the author’s creative process, methods, and practical research and draws conclusions about the role of the artistic experience in producing knowledge and informing audiences about the working principles of immaterial energies and invisible processes.
The research was inspired by the discovery of the photoacoustic effect by Alexander Graham Bell (1847–1922). In 1880, he invented the photophone, also known as the sun telephone. The invention was met with public criticism, but the nature of the phenomenon inspired Bell, so he continued his research, believing in its potential and possible artistic use.
The first experiments by the author on recording sound using light were done using simple and available materials and technology. A simple microphone was built with a mirror and a solar cell to record sounds with the sunlight. The mirror picks up voice and environmental sounds, and the reflected light is modulated accordingly. The research continued with building an interface that enables us to record voice and other sounds on paper visually. The next steps in the practical research concentrated on finding objects or phenomena that can be heard directly rather than using a mirror to pick up environmental sounds. The author discovered that it’s possible to hear the sound of insects moving their wings if their shadow is cast over the solar panel. This discovery was the basis for further research into finding methods of generating and amplifying sounds visually using vibrating strings, various rotating mechanisms, and flickering lights. The author developed instruments, created artworks, and did demonstrations, workshops, and performances that allowed visitors to participate in the process. Instruments were easy to use and allowed participants to understand their working principles in a way that allowed them to experiment and discover new sounds. The instruments and experiments demonstrate peculiarities of our perception – the flickering lights and the shadows of moving objects create the stroboscopic effect. The stroboscopic effect creates the illusion of the light being continuously on by visually slowing down the motion of the objects by dividing them into separate ‘frames’. The photoacoustic effect allows us to hear the connection between the flickering light and the slowed motion.
Media art researchers such as Armin Medosch (1962–2017) and Douglas Kahn (b. 1951) and others have analysed artworks that use electricity, electromagnetic waves, and other forms of energy that allow visitors to experience their presence and working principles. Khan refers to this type of artwork as ‘experiential physics’, believing that institutionalised science operates in ways that are too disconnected from people’s everyday experiences and realities. Philosophers Kšištof Pomian (b. 1934) and Edward Pols (1919–2005) emphasise the role of experience and perception in gaining knowledge.
Public workshops, performances, and demonstrations of the instruments and prototypes allow participants to experience the working principles of various immaterial phenomena (light, sound, electricity) and gain knowledge without using abstract models and theoretical explanations.