Bilberry and Night Vision

Are you familiar with the herb, bilberry. The package indicates this is used to improve night vision. Can you provide any information on this product or its affects on the body? Thank you.

Bilberry has astringent and anti-inflammatory properties and acts to strengthen the blood vessels, including those to the eyes. Thomas Bartram in "Encyclopedia of Herbal Medicine" (Grace Publishers, Mulberry Court, Stour Road, Christchurch, Dorset, BH23 1PS, England) states : "By stimulating production of colour purple improves vision, especially night vision".
As an astringent and anti-inflammatory, bilberry is useful in diarrhea. Being high in vitamins A and C, bilberries have been used to increase resistance to infection.