Since the advent of practical silicon photo-detectors more than 20 years ago, many people in the industry have been predicting with increasing regularity the imminent demise of the photomultiplier. Seen as being based on outdated technology, difficult to use, and requiring high voltages to operate, the days of the photomultiplier (PMT) are numbered. Or are they?
According to the organisers of the recent Invest in Photonics event held in Bordeaux, France, solid-state lighting looks likely to be a significant sector of the market for photonic technologies over the next few years. Given the concern of environmentalists around the world over the impact of climate change, and the push towards energy efficiency, efficient and long-lasting lighting based on LEDs is an attractive prospect.
When it comes to probing the secrets of matter, few tools have been as useful to chemists as the humble photon. By using sophisticated photonic devices called optical parametric oscillators (OPOs), modern chemists are able to produce photons at a wider range of wavelengths, and at a narrower bandwidth than ever before. In spectroscopy, different wavelengths of light correspond to different types of absorption within a chemical structure.
The short wavelength of UV, which makes it so suitable for certain applications, is the very thing that makes it difficult to work with as far as optics are concerned. Take semiconductor processing: being able to etch ever-smaller structures onto silicon chips requires shorter wavelengths to illuminate the lithographic mask. Advanced logic chips contain structures as small as 45nm, which is right at the boundary of what current lithographic illumination sources (typically excimer lasers operating at 193nm) can produce, because of the physical properties of light.
Making the leap from academia to the commercial world can be tough. The harsh realities of competition, coupled with a sudden need to understand economic challenges such as cashflow and credit, provide a stark contrast to the comparatively stable environment of a university research department.