| 摘要 |
<p>A modulated light source illuminates a target surface which possesses a certain color and shade of color. Light that is reflected from the target surface is detected by an optical detector. The output is compensated for any shift caused by ambient light, temperature of other external factors and demodulated to produce a substantially steady DC voltage that is indicative of the color or shade of color at the target surface. The steady DC voltage is converted using a look-up table or mathematical formula into a corresponding quantity or quality measurement such as analyte concentration, compensation being made for any variations in modulated light source intensity due to temperature change.</p> |
