What is S P ratio in lighting?

The S/P ratio is the ratio of luminous quantity in Scotopic wavelengths to luminous quantity in Photopic wave lengths for the lamp spectral power distribution. The Photopic and Scotopic luminous flux values are estimated by using Equation (1) and Equation (2) respectively shown below.

What is photopic lumens?

Photopic lumen output is the amount of light registered by the cones in the human eye and is measured by standard lumen and foot candle meters.

What is photopic Scotopic and Mesopic vision?

Scotopic and Photopic Vision Scotopic vision uses only rods to see, meaning that objects are visible, but appear in black and white, whereas photopic vision uses cones and provides color. Mesopic vision is the combination of the two and is used for most scenarios.

How is SP ratio calculated?

The S/P ratio was calculated according to the formula S/P ratio = 100 x CODsample/CODpositive reference serum. For each dilution tested (1/25, 1/50, 1/100) on each of the ELISAs, the ELISA titer as determined by regression was plotted against the S/P ratio, and a regression line was fitted to the plot.

What is Mesopic pupil?

Mesopic vision, sometimes also called twilight vision, is a combination of photopic and scotopic vision under low-light (but not necessarily dark) conditions. Mesopic levels range approximately from 0.01 to 3.0 cd/m2 in luminance. Most nighttime outdoor and street lighting conditions are in the mesopic range.

What is meant by photopic?

Definition of photopic : relating to or being vision in bright light with light-adapted eyes that is mediated by the cones of the retina.

What is mesopic lighting?

What is the mesopic range?

Mesopic: This term refers to a range of human vision with both rods and cones active. There is no hard-line transition at either end, but for most intents and purposes the mesopic range is generally considered to be from 3 cd/m2 down to 0.01 cd/m2.

What is a good cost to sales ratio?

The Price-to-Sales Ratio Analysts prefer to see a lower number for the ratio. A ratio of less than 1 indicates that investors are investing less than $1 for every $1 the company earns in revenue.

What is the time ratio?

Answer: The times interest earned ratio is an indicator of a corporation’s ability to meet the interest payments on its debt. The times interest earned ratio is calculated as follows: the corporation’s income before interest expense and income tax expense divided by its interest expense.

What is a photopic range?

Photopic vision is the vision of the eye under well-lit conditions (luminance levels from 10 to 108 cd/m2). In humans and many other animals, photopic vision allows color perception, mediated by cone cells, and a significantly higher visual acuity and temporal resolution than available with scotopic vision.