Specifications

Philips Fortimo HBMt Gen 3 System Design In Guide 31

Zhaga

Zhaga is a global consortium form by companies from across the lighting

industry. The overriding aim is to bring standardization to applications

in general lighting by creating welldened interface specications. This

ensures the interchangeability of LED light sources from different

manufacturers. All Fortimo LED high brightness module Gen2 (HBMt)

products are Zhaga certied. For more information on Zhaga, please

refer to the website: http://www.zhagastandard.org for complete details.

Luminance properties

The LED Module shall emit light of a Lambertian distribution in the

direction perpendicular to the mechanical reference plane. The luminance

distribution of the LLE is described by the following characteristics:

• Vertical symmetry

• Horizontal symmetry

• Center balance

• Uniformity

To enable a proper characterization of the luminance distribution, the

LES is subdivided into 8 areas A1 to A8, in which average luminance

is measured with an imaging luminance measuring device. Each of

these areas covers one eighth of the whole LES. These areas allow the

calculation of the above relevant uniformity factors without counting the

single LEDs which may be placed in an arbitrary variety inside the light

emitting surface.

Luminance Uniformity Parameter U

The uniformity parameter U is determined by rst calculating the average

and Root Mean Square (RMS) of the Luminance Lj of every pixel j inside

the LES whereby N equals the number of pixels:

Lavg= (∑ Lj) /N

LRMS= √(∑ (Lj)2 ) /N)

The uniformity parameter U is calculated as U = Lavg / LRMS

Maximum total thermal power of the module

Maximum thermal power generated by the LED module (unit: W). The

maximum thermal power equals the maximum electrical power (unit: W)

that is supplied to the LED module minus the minimum optical power

(unit: W). The optical power (Pvis,unit: W) is the radiant ux of the LED

module in the wavelength range from 380nm up to 780nm (unit: W).

Zhaga Book 4: Flat emitter streetlight module

Figure 31. Zhaga logo