GB2325048A - Measurement of sun protection factor - Google Patents

Abstract

A meter for determining sun protection factors measures the levels of ultra violet rays and relates these measurements to sun protection factor of lotions and sunscreens. Photodiodes 9 and 10 are connected through push to make switches 1-4 and respective adjustable resistors to a meter 11. The switches 1-4 may be push to make and relate to different skin types. The casing may be cylindrical with the meter and a photodiode mounted on one end. The sun protection factor is calculated by the manufacturers, many of which use different standards, but are all based on how long it takes for unprotected skin to burn, average length of time = 10 minutes.

Description

An Apparatus for Measurement of Sun Protection Factor This invention relates to an apparatus for measurement of sun protection factor, and more particularly to a meter which will provide a measurement of ultra violet rays produced by the sun.

Sunscreen lotions have a sun protection factor from 2 - 60+, the higher the sun protection factor the greater the degree of protection. If a sun protection factor lotion is applied to skin and the factor number is 20, this number is multiplied by 10 minutes, the protection offered (10 minutes x 20) = 200 minutes.

It is essential to know your own skin type when using sunscreen, children need a sun protection factor of 15 or more when playing outdoors during the hottest part of the day.

Skin types are usually described according to natural levels of pigment and how it reacts to sunshine. Skin type 1 always burns and never tans, skin type 2 frequently bums and sometimes tans, skin type 3 sometimes bums and frequently tans, skin type 4 never bums and always tans, skin types 5 and 6 are very tolerant to sunshine and are usually Asian and black skin colouring.

The accompanying drawings show by way of example a constructional form of the invention in which: fig 1 is a top view of the cover plate fig 2 is a side view of the box fig 3 shows an alternative method of measuring sun protection factor In the figures, the reference numeral 17 denotes the cylindrical casing of the apparatus, fig 4 shows a top view.

With reference to fig 3, the reference numeral 12 denotes a meter, 15 is a photo diode, 13 is an electrical push to make switch which denotes the ultra violet levels, 14 is a push to make electrical switch which measures the sun protection factor.

With reference to fig 1 denoting a top view of the cover plate, the reference numeral 12 denotes a rectangular cover plate, 11 is a meter, 9 and 10 are photo diodes, 1, 2, 3 are push to make electrical switches, 4 is a push to make electrical switch, this shows levels of ultra violet rays.

Fig 2 denotes a side view of a rectangular box construction, 1, 2, 3 are push to make electrical switches; these switches denote the skin types: switch 1 is for number 1 skin type switch 2 is for number 2 skin type switch 3 is for number 3 skin type switch 4 is for detecting levels of ultra violet rays Fig 5 denotes an electrical circuit with reference to fig 1 and fig 2 Fig 6 denotes an electrical circuit with reference to fig 3 and fig 4 With reference to fig 5 numerical numbers 1, 2, 3, 4 are electrical push to make switches; 5, 6, 7, 8 are adjustable resistors; 9, 10 are photo diodes; 11 is a meter.

With reference to fig 6 numerical numbers 1, 2 and push to make electrical switches; 3, 4 are adjustable electrical switches; 5 is a photo diode, 6 is a meter.

Claims (2)

1. Claims

   Having now particularly described the nature of my said invention, I declare that what I claim is:1. An apparatus for measurement of sun protection factor meter, comprising of a meter and photo diodes and adjustable resistors, with means to determine the levels of ultra violet light levels.
2. 2. An apparatus for determining the skin types with reference to sun protection factors according to claim 1.