Slit lamp review: New device in the spotlight

There have been a surprisingly few significant changes to slit-lamps over the decades. The basic design of a Galilean binocular microscope rotating about a common centre of rotation with a light source remains in both the two standard (Haag-Streit and Zeiss style) set ups. Image quality has evolved with better lens design and coating, the range of filters available has extended, in particular the introduction of the essential orange/yellow absorption filter (discussed later), and LED light sources have better efficiency and no heat emission. The incorporation of increasingly simple to use cameras and easy to manipulate image software makes many aspects of modern optometry clinic work better to be standardised, recorded and used to educate patients.