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gec full range | refractors




holophane prismatic glass refractor
The Metropolitan lantern is described as using a Holophane refractor.
Z???? ???W
??? ???° ???° 1928 Journal Metropolitan FA 8169-70
Metropolitan FA 8169-70






symmetric one-piece prismatic glass refractor
Used extensively by the Wembley system.
Z???? ???W
Symmetrical ???° ???° 1928 Journal GEC Wembley








asymmetric one-piece prismatic glass refractor
Described as new in 1928. The magnification factor at the peak angle attains 6.5, and this characteristic is favourable to the attainment of uniform illumination between posts. It is fashioned in a double prismatic formation on one thickness of glass, an arrangement which is conducive to minimum loss of light. Its main object is, of course, to direct on the roadway rays, whcih would otherwise pass upwards and be lost. Another special feature is the elliptical shape. The major axis is at right angles to the street, a condition which is very favourable to the use of refractors of the asymmetric type. These new refractors are interchangeable with the standard GEC symmetrical on-piece prismatic refractors as fitted to the standard Wembley lanters.
Z???? ???W
Symmetrical ???° ???° 1928 Journal GEC Wembley





symmetric glass dome refractor

Symmetric dome refractor. Described as new in 1933 and first given catalogue number G 501.
G 501 60-200W
Symmetrical 70° - 1933 catalogue GEC Wembley F 5441
GEC Wembley F 5445
GEC Wembley F 5451
GEC Wembley F 5455


Z 6501 60-200W GLS
80-125W MBF/U
Symmetrical - - 1937 catalogue GEC Enclosed Wembley Z 5001
GEC Enclosed Wembley Z 5004
GEC Enclosed Wembley Z 5011
GEC Enclosed Wembley Z 5014
GEC Open Wembley York Z 5041 GEC Open Wembley York Z 5051 GEC Open Wembley Sheldon Z 5061 GEC Open Wembley Sheldon Z 5071 GEC Open Wembley Norwich Z 5081
GEC Open Wembley Norwich Z 5091
GEC Small Oxford Z 5515
GEC Small Oxford Z 8155


Z 6503 300-500W GLS
Symmetrical - - 1937 catalogue GEC Enclosed Wembley Z 5021
GEC Enclosed Wembley Z 5024
GEC Open Wembley Hull Z 5101
GEC Oxford Z 5525


Z 6505 1000-1500W GLS
Symmetrical - - 1937 catalogue GEC Enclosed Wembley Z 5031
GEC Enclosed Wembley Z 5034
GEC Open Wembley Hull Z 5111





non-axial asymmetric glass dome refractor

Non-axial asymmetric dome refractor. Described as new in 1933 and first given catalogue number G 507.
G 507 60-200W
Non-axial asymmetric 75° - 1933 catalogue GEC Wembley F 5442
GEC Wembley F 5446
GEC Wembley F 5452
GEC Wembley F 5456


Z 6507 60-200W GLS
Non-axial asymmetric - - 1937 catalogue GEC Enclosed Wembley Z 5002
GEC Enclosed Wembley Z 5005
GEC Enclosed Wembley Z 5012
GEC Enclosed Wembley Z 5015
GEC Open Wembley York Z 5042 GEC Open Wembley York Z 5052 GEC Open Wembley Sheldon Z 5062 GEC Open Wembley Sheldon Z 5072 GEC Open Wembley Norwich Z 5082
GEC Open Wembley Norwich Z 5092


Z 6509 300-500W GLS
Non-axial asymmetric - - 1937 catalogue GEC Enclosed Wembley Z 5022
GEC Enclosed Wembley Z 5025
GEC Open Wembley Hull Z 5102


Z 6511 1000-1500W GLS
Non-axial asymmetric - - 1937 catalogue GEC Enclosed Wembley Z 5032
GEC Enclosed Wembley Z 5035
GEC Open Wembley Hull Z 5112





axial asymmetric glass refractor

Axial asymmetric dome refractor. Described as new in 1933 and first given catalogue number G 513.
G 513 60-200W
Axial asymmetric 75° - 1933 catalogue GEC Wembley F 5443
GEC Wembley F 5447
GEC Wembley F 5453
GEC Wembley F 5457


Z 6513 60-200W GLS
Axial Asymmetrical - - 1937 catalogue GEC Enclosed Wembley Z 5003
GEC Enclosed Wembley Z 5006
GEC Enclosed Wembley Z 5013
GEC Enclosed Wembley Z 5016
GEC Open Wembley York Z 5043 GEC Open Wembley York Z 5053 GEC Open Wembley Sheldon Z 5063 GEC Open Wembley Sheldon Z 5073 GEC Open Wembley Norwich Z 5083
GEC Open Wembley Norwich Z 5093


Z 6515 300-500W GLS
Axial Asymmetrical - - 1937 catalogue GEC Enclosed Wembley Z 5023
GEC Enclosed Wembley Z 5026
GEC Open Wembley Hull Z 5103


Z 6517 1000-1500W GLS
Axial Asymmetrical - - 1937 catalogue GEC Enclosed Wembley Z 5033
GEC Enclosed Wembley Z 5036
GEC Open Wembley Hull Z 5113








plate refractor
First used for vertically burning MA lamp frame-type lanterns. Mainly just a "spreader" or diffuser with vertical glass flutes. Smaller size for 150W and 250W MA/V lamps.
Z 6300 150-250W
Asymmetrical ???° ???° 1937 Catalogue GEC Small Watford Z 8007/8








plate refractor
First used for vertically burning MA lamp frame-type lanterns. Mainly just a "spreader" or diffuser with vertical glass flutes..
Z 6301 ???W
Asymmetrical ???° ???° 1935 Catalogue GEC Watford Z 8001
GEC Lewisham Z 8003
GEC Tunbridge Wells Z 8005
GEC Post Top Tunbridge Wells Z 8055
GEC Birchfield Z 8009








opal bowl diffuser
First used for vertically burning MA lamp lanterns. The diffusing bowl is of high quality low absorption flashed opal white glass. The special shape of the glass is not only decorative, but has been designed to give a good distribution of candle-power for the general lighting of such areas as traffic junctions where a diffused light is required..
Z 6466 150W MA/V
Dispersive - - 1937 Catalogue GEC Small Di-Fuser Z 8104
Z 6468 250-400W MA/V
Dispersive - - 1935 Catalogue
1937 Catalogue
GEC Di-Fuser Z 8124
GEC Post-Top Mounting Di-Fuser Z 8224
GEC Wembley Conversion Unit FC 6047








single piece reflector refractor
The reflector contour is based on the design of the well known G.E.C. P.L.A. lantern, whilst the prisms mounted on the bottom band are of identical design to those on the G.E.C. prismatic bowl refractor and produce a 160° non-axial asymmetric light distribution. The prismatic refractor contols in plan the light which is reflected from the silvered portion of the glass, and well as direct light from the lamp, thus providing a very efficient optical system..
Z 6557 60-200W GLS
80-125W MB/V
Non-axial asymmetric ???° 160° 1937 Catalogue GEC Pla-Fractor Z 8405








well glass (clear)
Used for vertically burning MA lamp lanterns. Not recommended for street lighting.
Z 6481 400W MA/V
Symmetrical ???° ???° 1935 Catalogue GEC Z8500
GEC Z8501
GEC Z8502
GEC Z8503
Z 6484 250W MA/V
Symmetrical ???° ???° 1935 Catalogue GEC Z8510
GEC Z8511
GEC Z8512
GEC Z8513








bowl refractor-diffuser

British Patent Number: 408419

The bowl refractor illustrated above has been designed, developed and perfected at the G.E.C. Research Laboratories. It embodies the G.E.C. patented principle of a concentrating refractor used in conjunction with a ribbed diffuser combined in one single piece of accurately-made prismatic glassware of pleasing proportions. The main controlling prisms, manufactured with extreme accuracy, redirect the light up and down the road in two main beams which, being at 160° to each other, project the light slightly diagonally across the road. These prisms are moulded inside the bowl and are, therefore, protected against dirt and dust, consequently they only required to be cleaned after long intervals, thus reducign the cost of maintenance. On the outside of the bowl are moulded a series of shallow flutes and prisms which give the correct amount of diffusion in the light in the main beams, thereby making the whole outside of the bowl appear evenly flashed. Further, the light in the downward direction is controlled by a special diffusing surface consisting of small graduated cones of carefully calculated angles, the effect of these being to distribute more light immediately under the lantern, so preventing the occurrence of a dark patch normally present beneath lanterns without this feature.

The result of the combination of these two optical systems is to produce continuous lanes of road brightness, giving maximum silhouette and consequently long distance road visibility, and also to make the lantern bowl appear evenly flashed, thereby eliminating glare. A less accurately designed refractor without these diffusing prisms would be flashed over a small area only, and in consequence glare is produced. The external diffusing flutes on the G.E.C. bowl refractor are very shallow and do not interfere in any way with the cleaning of the glassware, and this also applies ot the somewhat deeper external prisms. In this connection, it is interesting to note that even though the prisms on the outside of the bowl are easily cleaned and the flutes are so shallow as to be self-cleaning, should dirt collect in the "VEE" formed by prisms the light distribution will not be affected. This is due to the fact that rays of light emerge only from the tips of the prisms due to the special optical system employed.

The glass from which the bowl is made is the result of very extensive research by the G.E.C. Laboratories, and besides having the required optical properties it has the highly desirable feature that it will not fracture when subjected to rain splash when it is employed with the recommended lamps. This is a most important consideration in view of the temperature which is produced inside the bowl. The locating device moulded on the bowl refractor ensures correct alignment of the refractor in relation to the roadway and arrows indicating the direction of the main beams can be seen on the underside of the bowl, so that it is a simple matter to ascertain that the bowl has been corrected fitted.

The manufacture of this bowl refractor is a great advance in pressed prismatic glassware and it is unique in that its is the largest pressing made incorporating the internal refracting prisms with external diffusing flutes and prisms. This combination results in the minimum of light absorption as the loss which occurs in two-piece refractors is avoided. In the latter type, as the result of breathing every time the lamp is switched off, dust and dirt are deposited on the two inside surfaces and further absorption takes place due to condensation.

When this bowl refractor unit is used in conjunction with OSRAM metal filament lamps certain modifications have to be made to the optical system. The bowl refractor is designed for use witha thin vertical light source such as is produced by the OSIRA lamp, but, as the metal filament lamp radiates its light in a horizontal plane, it is necessary to change the distribution from the horizontal to a vertical shape, and this can be easily accomplished by the introduction of an inner symmetric dome refractor. This form of optical system is extremely efficient for use with OSRAM gasfilled lamps when at the time only a D.C. supply system is available, and has the very great advantage that when the supply is converted to A.C. the optical system can also be converted for use with OSIRA lamps, which can then be employed on the new supply. The conversion is simply carried out by the removal of the inner dome refractor and the substitution of the vitreous enamelled reflector with one of a suitable shape. This operation, which only occupies a few minutes, can be done with the lantern in-situ and without any alteration to the wiring.

Z 6607 150W MA/V
80-125W MB/V
Asymmetrical ???° 160° 1937 Catalogue GEC Small Oxford Z 5515
GEC Small Di-Fractor Z 8105
GEC Small Oxford Z 8155
Z 6609 250-400W MA/V
Asymmetrical ???° 160° 1935 Catalogue
1937 Catalogue
GEC Di-Fractor Z 8122
GEC Di-Fractor Z 8125
GEC Di-Fractor Z 8128
GEC Post Top Mounting Di-Fractor Z 8225
GEC Wembley Conversion Unit FC 6047
GEC Oxford Z 5525








outer globe
Clear "acorn shaped" outer globe.

Z 6465 60-200W GLS
Symmetrical - - 1937 Catalogue GEC Wembley Z 5001/16
Z 6467 300-500W GLS
Symmetrical - - 1937 Catalogue GEC Enclosed Wembley Z 5021/3
GEC Enclosed Wembley Z 5024/6
Z 6469 1000-1500W GLS
Symmetrical - - 1937 Catalogue GEC Enclosed Wembley Z 5031/3
GEC Enclosed Wembley Z 5034/6






rimpled outer globe
These rimpled outer globes have been specially produced to repace the normal clear outer globes Z 6465/67 as used on the small "Wembley" lanterns, where a rather more decorative appearance is required. It is desired to make use of existing small "Wembley" lanterns for 80 and 125-watt OSIRA H.P. Mercury Vapour lamps, it is essential to use rimpled outer globes. Their employment produces a slightly diffuse effect without distortion of the light distribution, thus preventing glare, which would be present if a clear globe was used.
Z 6475 60-200W GLS
80-125W MBF/U
Symmetrical - - 1937 Catalogue GEC Wembley Z 5001/16
Z 6477 300-1500W GLS
Symmetrical - - 1937 Catalogue GEC Enclosed Wembley Z 5021/3
GEC Enclosed Wembley Z 5031/3