luminance

IPA/ˈluːmɪnəns/
KK[lˈumənəns]IPA/ˈluːmɪnəns/

luminance — noun

1. In physics and engineering, a measurement of how much light a surface sends out

1.名詞C1
釋義

In physics and engineering, a measurement of how much light a surface sends out toward a viewer, calculated for each unit of area from a specific angle.

例句

The technician recorded the LED panel's luminance at 350 candelas per square meter.

collocation: recorded at + value in candelas per square meter

Harper adjusted the lamps until the model's skin luminance matched the afternoon light.

adjusted until + target luminance matched

同義詞
  • brightness

    Everyday term; luminance is the precise technical measurement that brightness roughly corresponds to.

  • intensity

    Broader term covering any light strength; luminance is specific to directional surface emission.

  • radiance

    Used in radiometry for electromagnetic radiation; luminance is the photometric (visible-light) equivalent.

文法句型

the + luminance + of + noun

用法筆記

In technical fields, luminance is measured in candelas per square metre (cd/m²) or nits. Do not confuse with illuminance, which measures light that falls onto a surface rather than light sent out from one.

常見錯誤

❌Set the luminance of the room to 50 lux.
✅Set the luminance of the screen to 50 cd/m².
💡luminance uses candelas per square metre, not lux (which measures illuminance).

2. The quality of shining or appearing bright because a surface either produces its

2.名詞C1
釋義

The quality of shining or appearing bright because a surface either produces its own light or reflects light from another source.

例句

Jiwoo's pearl earrings had a soft luminance that caught the light as she turned.

collocation: soft luminance

After a polish, the brass handles on the old door showed a warm golden luminance.

luminance produced by polishing metal

同義詞
  • lustre

    Describes the gentle shine of a polished surface; more poetic than luminance.

  • glow

    Suggests a warm, steady light; less precise than luminance.

  • sheen

    A soft shine on a surface, often from oil or polish; narrower in use.

反義詞

文法句型

the + luminance + of + noun

用法筆記

This sense is common in descriptive writing about art, jewellery, nature, and reflective surfaces. Unlike sense 1, it does not refer to a measured scientific value.