1,492
edits
Andrei.boiu (talk | contribs) m (→Suitability) |
Andrei.boiu (talk | contribs) |
||
| (3 intermediate revisions by the same user not shown) | |||
| Line 24: | Line 24: | ||
|style="vertical-align:top" | | |style="vertical-align:top" | | ||
[[Image: | [[Image:Osram HQI-TS 70W.jpg|Osram HQI-TS 70W]] | ||
|} | |} | ||
</div> | </div> | ||
| Line 93: | Line 93: | ||
| High light output in very compact package || Hot operating fixtures, maintenance intensive | | High light output in very compact package || Hot operating fixtures, maintenance intensive | ||
|- | |- | ||
| High efficiency, good colour rendering || | | High efficiency, very good colour rendering || Relatively low lamp service life | ||
|- | |- | ||
| Directional light || Sensitive to operating position and unbalanced wearing | | Directional light || Sensitive to operating position and unbalanced wearing | ||
| Line 118: | Line 118: | ||
The lamp technology was an improvement of previously developed mercury vapour lamps. The potential for fluorescent powders was mostly exhausted by early 70s which meant that research concentrated on releasing better lamps that produced light directly from the discharge tube. This research was also carried previously but results were modest, as stable compounds with good colour reproduction were found to be quite aggressive and lead to short service life. Sodium, Scandium, Indium, Thallium were attempted as main elements that can offer a balanced light output but they required a specific balance of temperature and pressure to achieve best results. One major limitation was that certain compounds were costly or difficult to manufacture or mix in specific amounts, which meant that suitable results could not be found for many decades. In the late 70s and early 80s most major manufactures were able to center on specific technologies that reached good enough results for general lighting, with predictable performance. | The lamp technology was an improvement of previously developed mercury vapour lamps. The potential for fluorescent powders was mostly exhausted by early 70s which meant that research concentrated on releasing better lamps that produced light directly from the discharge tube. This research was also carried previously but results were modest, as stable compounds with good colour reproduction were found to be quite aggressive and lead to short service life. Sodium, Scandium, Indium, Thallium were attempted as main elements that can offer a balanced light output but they required a specific balance of temperature and pressure to achieve best results. One major limitation was that certain compounds were costly or difficult to manufacture or mix in specific amounts, which meant that suitable results could not be found for many decades. In the late 70s and early 80s most major manufactures were able to center on specific technologies that reached good enough results for general lighting, with predictable performance. | ||
The | The HQI-TS range was the result of research aimed at creating lower powered metal hallide lamps that had better colour reproduction and energy efficiency compared with high pressure mercury vapour lamps. The most important limiting factor was that the arc tube had to be formed more evenly at the ends and be reasonably well insulated and heat resistant to ensure reasonable performance. More advanced manufacturing tools and processes had to be developed. The arc tube was well built to resist the long term corrosive nature of hallides. It was also important to ensure less variations in arc tube geometry as well as temperature profile. This meant that heat reflecting coatings were mandatory for the arc tube. As soon as all these conditions were met, the lamp was released. Osram had superior manufacturing technology that allowed better performing lamps although they were also more expensive to manufacture due to less marketshare. | ||
Products were quite successful on the market until the advent of the much improved ceramic tube metal hallide lamps, around mid 1990s. Although ceramic hallide lamps were much more expensive, their better colour reproduction, lamp life and efficiency meant that there were few reason to choose HQI-TS lamps. However, the higher wattage and white appearance choices made this lamp range more appreciated on the market than the Philips MHN-TD lamps, especially on markets where performance was favoured more than cost and Osram had a good presence. Although less affected than Philips , Osram HQI-TS lamp installations were experiencing a slow demise as the LED light sources were taking over the market in late 2000s. | |||
== Manufacturing specificities == | == Manufacturing specificities == | ||
Most manufacturers have been releasing lamps for many decades and constantly improved technology so that lamps had a stabler, predictable lifetime and slightly improved colour stability due to manufacturing progress. | Most manufacturers have been releasing lamps for many decades and constantly improved technology so that lamps had a stabler, predictable lifetime and slightly improved colour stability due to manufacturing progress. | ||
Compared with Philips MHN-TD lamps, the HQI-TS range is much more diverse, offering a wider selection of wattages as well as more white colour choices. Also, another advantage of Osram products is that service lifetime is improved by around 2000 hours and that daylight colour lamps are very good for accurate daylight colour reproductions, with a light that closely mimics the ideal 5500K colour temperature standard. Osram HQI-TS lamps were not as widely used as MHN-TD lamps but they are a much better purchasing choice. | |||
{{footnotes| | {{footnotes| | ||