Abstract: A lotion such as a sunscreen includes a pH indicator which colorizes the lotion until the lotion is applied to the human skin, whereinafter the colored lotion turns clear. A physiologically compatible pH indicator such as phenolphthalein is used which has a red appearance from pH 7.5+ and which has a clear appearance from about pH 7.0 to 7.5, the general pH range of the skin. The invention is suitable for use in any lotion, gel, mousse or medication that is best applied in an even and uniform manner to the skin. Accordingly, one preferred use of the invention is in UV-protecting sunscreens so that a user can ensure even distribution of the sunscreen on the body. In certain aspects of the invention, a cap houses the pH indicator and attaches to a container of the lotion, e.g., a sunscreen. The pH indicator mixes with the lotion as it is applied to the skin.

Abstract: A lotion such as a sunscreen includes a pH indicator which colorizes the lotion until the lotion is applied to the human skin, whereinafter the colored lotion turns clear. A physiologically compatible pH indicator such as phenolphthalein is used which has a red appearance from pH 7.5+ and which has a clear appearance from about pH 7.0 to 7.5, the general pH range of the skin. The invention is suitable for use in any lotion, gel, mousse or medication that is best applied in an even and uniform manner to the skin. Accordingly, one preferred use of the invention is in UV-protecting sunscreens so that a user can ensure even distribution of the sunscreen on the body. In certain aspects of the invention, a cap houses the pH indicator and attaches to a container of the lotion, e.g., a sunscreen. The pH indicator mixes with the lotion as it is applied to the skin.

Abstract: An ultraviolet radiation detection exposure system determines either ultraviolet flux or accumulated ultraviolet energy. A detector converts the ultraviolet radiation into voltage, and a voltage-to-frequency converter provides a corresponding frequency. If the system measures flux, a conversion subsystem converts the frequency to an associated ultraviolet flux in watts. If the sensor measures ultraviolet energy over a period of time, a counter counts at the frequency of the voltage-to-frequency converter thereby integrating the received ultraviolet energy at the detector. A reset button allows the user to reset the system, clearing the counter, prior to entering the sun for the day. A warning light, display, or buzzer indicates to the user of the system that her skin is in danger of receiving a sun burn. A plurality of fibers and/or lambertian half-spheres are used to provide substantially uniform solar acceptance. A solar cell can be used to power the apparatus, especially within a watch configuration.