Skip to main content

Table 4 Proposed combinations of FOMs

From: A multi-functional design approach and proposed figure of merits for solid state lighting systems

FOM Formula Unit Description
FOMR ΔT/q K/W Thermal resistance
FOMR,m ΔT m/q K kg/W Thermal resistance based on mass
FOMR,A ΔT A/q K cm2/W Thermal resistance based on surface area
FOMR,m,A ΔT m A/q K kg cm2/W Thermal resistance based on mass and surface area
FOMLPW Φ/P lm/W Luminous efficacy
FOMLPW,m Φ/P m lm/W kg Luminous efficacy based on mass
FOMLPW,A Φ/P A lm/W cm2 Luminous efficacy based on surface area
FOMLPW,m,A Φ/P m A lm/W kg cm2 Luminous efficacy based on mass and surface area
FOMT,L ΔT/Φ K/lm Opto-thermal resistance
FOMT,m,L ΔT m/Φ K kg/lm Opto-thermal resistance based on mass
FOMT,A,L ΔT A/Φ K cm2/lm Opto-thermal resistance based on surface area
FOMT,m,A,L ΔT m A/Φ K kg cm2/lm Opto-thermal resistance based on mass and surface area
  1. Subscripts
  2. A, Area (cm2).
  3. L, Luminous flux (lm).
  4. LPW, Lumen per watt (lm/W).
  5. m, Mass (kg).
  6. P, Power (W).
  7. R, Thermal resistance (K/W).
  8. T, Temperature (°C).