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Tony's Intertwingled Memex • Reference Manual

Optoelectronic LED Display Panel Average Irradiance (Entertainment & Electrical Engineering)

Formulas & Definitions

An entertainment and electrical systems engineer at the UNLV Howard R. Hughes College of Engineering is designing a modular, high-dynamic-range LED stage display panel for an interactive performance venue on the Las Vegas Strip.

The modular rectangular panel measures 0.5 m0.5\text{ m}0.5 m in width along the xxx-axis and 0.4 m0.4\text{ m}0.4 m in height along the yyy-axis, occupying the closed rectangular domain:

R=[0,0.5]×[0,0.4](units in meters)R = [0, 0.5] \times [0, 0.4] \quad (\text{units in meters})R=[0,0.5]×[0,0.4](units in meters)

Because of resistive thermal heating along the internal power busbars and localized LED driver clustering, the emitted radiant surface irradiance E(x,y)E(x, y)E(x,y) is non-uniform across the panel surface and is characterized by the empirical polynomial model:

E(x,y)=E0(1+4x2y)(W/m2)E(x, y) = E_0 (1 + 4x^2y) \quad (\text{W/m}^2)E(x,y)=E0​(1+4x2y)(W/m2)
where E0E_0E0​ is the baseline radiant irradiance measured at the origin corner (0,0)(0, 0)(0,0) in watts per square meter (W/m2\text{W/m}^2W/m2).

To prevent visible optical brightness banding (hotspots) and to calibrate the overall electrical power supply feeding the stage wall, the engineering team must determine:

  1. The total surface area Area(R)\text{Area}(R)Area(R) of the modular display panel.
  2. The total radiant luminous flux Φ=∬RE(x,y) dA\Phi = \iint_R E(x, y) \, dAΦ=∬R​E(x,y)dA emitted across the active face of the panel, evaluated as an iterated double integral using Fubini's Theorem.
  3. The spatial average irradiance EavgE_{\text{avg}}Eavg​ across the entire panel expressed as a multiple of the baseline irradiance E0E_0E0​.
  4. The physical engineering interpretation of the ratio Eavg/E0E_{\text{avg}} / E_0Eavg​/E0​ and how it informs optical diffuser film selection.