Typical Rectangular Woods Lamp Made by Waldmann

Perhaps a little off topic. The Black Light or the Woods Light is a low energy ultraviolet emitter  usually at 365 nm. All kinds of DNA based materials fluoresce when illuminated by a UV source. In fact one of the primary uses of a Woods Light is in the detection and determination of Vitiligo. Vitiligo is a skin condition where the skin becomes depigmented and turns white. The resulting white spots glow brightly in the presence of the light from a Woods Lamp.

Vitiligo on Hands

To see a selection of images where the skin fluoresces. Click here http://msp.rmit.edu.au/Article_01/14_gallery.html. Vitiligo is an equal opportunity  disease affecting 1% to 2% of the world’s population. We tend to notice it more in dark skinned people because of the greater contrast between the light and dark skin tones. Materials that fluoresce are materials that are affected by the UV light and they themselves emit light. If you’ve ever entered a bar with black lights over the dance floor, you’ve seen how some fabrics and other items glow in the presence of UVA / Black Light.

 Typical Applications for Woods Lamps or Woods Light are very diverse. In the medical field there are several applications. We also find them used in criminology (forensics), mineralogy and gemology to detect fluorescence in many minerals and gems.

We will attempt here to list some of the major applications of our woods lights or woods lamps.

Medical Uses

Several skin diseases/challenges such as vitiligo, acne and a host of others cause the skin (or the fluids on the skin) to fluoresce.

• Vitiligo
• Bacterial Infections
• Acne
• Porphyria
• Erythasma 
• Alopecia
• Tinea Versicolor
• Fungus & Fungal Infections
• Head Lice and their nits, fluoresce under black light.
• Ringworm
• Scabies
• Child abuse / bruising can often be discerned with a woods light.

Why is it useful to be examined with the Wood’s lamp? Normally your skin will not fluoresce, or shine, under the ultraviolet light. This test reveal different colors according to the type of skin disease, which may include:

• Golden Yellow (Tinea Versicolor)
• Pale Green (Trichophyton Schoenleini)
• Bright Yellowgreen (Microsporum Audouini or M. Canis)
• Aquagreen To Blue (Pseudomonas Aeruginosa)
• Pink To Pinkorange (Porphyria Cutanea Tarda)
• Ash-Leaf-Shaped Spot (Tuberous Sclerosis)
• Bluewhite (Leprosy)
• Pale White (Hypopigmentation)
• Purplebrown (Hyperpigmentation)
• Bright White, Or Bluewhite (Depigmentation, Vitiligo)
• Bright White (Albinism)

Ophthalmology

When used with sodium fluorescein or other fluorescing dyes, there are several applications for the world of the eye doctor.

• Foreign Particles in the Eye (glass and other hard to see particles)
• Eye Injury
• Scratches of the cornea
• Blocked Tear Ducts

Veterinary Applications

• Ringworm
• Urine Stains
• Eye challenges
• Lice and Nits
• Microsporum Canis
• Fungal Infections

Miscellaneous Uses

• Pets, small and large leave urine and feces in places that you would least expect. Feces, urine and other biological contaminants/materials can be detected easily with UVA Woods Lights.
• Hard water detection. Many “Culligan Men”, water softener sales people carry a UVA black light as many hardened mineral deposits on taps, sinks etc fluoresce with black light.
• Re-admittance inks. Fluorescent Ink detection. Some invisible inks such as those uses at some night clubs and amusement parks for re-entry stamps can ne seen under UV (Black Light)
• Rodent urine and traces fluoresce under black light. One can monitor/detect some forms of rodent activity with a simple woods lamp.
• Fraud detection. Some of our money has fluorescent dyes within.