||The Osram 'Accent' lamp was introduced in 1971 as a new direction in decorative indoor lighting, marking the first occasion that British and European markets were offered a square incandescent lamp. Its styling must surely have been inspired by the slightly more rounded Westinghouse lamps which were introduced some years earlier in America.
Accent lamps were produced with a soft white internal coating, the same as had been applied previously to the GEC's 'Filtalite' Mushroom shaped lamps. In the GEC coating process, which pre-dates the introduction of electrostatically applied powders, an improvement was made over the previous wet-coatings by spraying titanium tetrachloride into a heated glass bulb. On contact with the hot glass this was hydrolised to form the powerful white dye, titanium dioxide. The resulting particles are so small as to have an interesting diffraction effect, with blue light being scattered more than red. This leads to the glare spot of the filament appearing much warmer than usual which is particularly noticeable in the dimmed state, and leads to a very pleasant low-glare light source. Thanks to the bulb volume being some 70% greater than the mushroom shape white coated lamps, both glare and glass surface temperatures are considerably lower.
Incidentaly, this Accent model was the first British lamp to be manufactured in a full colour corrugated sleeve, thanks to a new printing process that was developed. Later, the lamp was offered in coloured versions, and a double life version was also made. Around 1989 the bulb shape was changed to the smaller and more rounded Westinghouse / Philips T60 design, becauase the sharp corners of this T65 bulb were leading to excessive breakage in production.