Technology May Make Paintings More Accessible for Persons with Visual Impairment

May 30, 2020

As tempting as it may be, you can’t touch a painting in a museum. And now that many museums are closed, you’re even further from seeing the close-up detail in brush strokes that can tell you so much about how the art was created.

But now, a collaboration between artists and researchers at Penn State and the New Jersey Institute of Technology have come closer to developing a method that makes it possible to scan a sizeable section of a painting and turn it into a 3-D model that maintains the fine brush stroke pattern details. This technology could help improve online art lessons and virtual museum tours as well as make paintings more accessible to visually impaired people.

The main technology they used in this new scanning strategy is optical coherence tomography (OCT). Although OCT has been used in art analysis before, to study the top paint or varnish layers, the technology wasn’t developed with art historians in mind. OCT was created for medical research, for example for detailed 3-D imaging of small parts of the human body. It’s commonly used to take images of the back of the eye, for instance, to monitor the health of someone’s retina.

"Because today's OCT systems are optimized for biomedical applications, they have a limited scanning range that severely limits the speed of collecting data from large areas," lead researcher Yi Yang from Penn State Abington told The Optical Society, who published the study.

With the painting lying on the platform, the scanner first visualized the 3-D pattern of the paint in a very small area of the painting, approximately three by four millimeters. After the first segment was complete, the stage moved the painting so that an adjacent area appeared in the field of view of the OCT scanner, and the process started again.

After 90 small segments of the painting were scanned, they needed to be merged together to create the final image of the total 27mm x 18 mm area (approximately 0.75 square inch) that had been scanned. For this, the engineers developed software that stitches together the separately scanned regions with minimal noise artefacts. The result is a detailed rendering of the three-dimensional brush stroke pattern in this area of the painting.

Because this system makes it easier to collect detailed information of the paint layers for larger areas of paintings, the researchers propose that it could be used to improve the digital archive information of artworks to preserve them as much as possible in the event of damage.

But another potential application for this technology could be art education. Whether it’s through online classes or virtual museum tours, many art students and museum fans are currently looking for digital ways to get closer to the art. This new method would allow them to digitally rotate and zoom in on certain structures in the paint.

And finally, the low-noise digital stitching software makes it possible to turn the virtual renderings into 3-D-printed physical objects that mimic the texture of the paint. That could be interesting for museums who want to make their exhibits more accessible, by allowing visually impaired visitors to get closer to the art.

So even though you still can’t touch a painting in a museum, touching a 3-D-printed replica of that painting’s brush stroke pattern might be possible soon.

Source: Forbes