Lakshmi is the energy associated with Lord Vishnu.
	Lakshmi is derived from Lakshma, which means a symbol. It is not possible to point out exactly which symbol represents Lakshmi and from which symbol She may be perceived.
	A substitute for Lakshmi is the word "Shri", which means decoration or luster. Since the word Shri is derived from the symbol svastik, it seems quite likely that the symbol representing Lakshmi must be the svastik. One comes across both the words Shri and Lakshmi in the Rugveda. The Shrisukta, an appendix of the Rugveda, is quite famous. Deity Lakshmi is worshipped with the Shrisukta itself.' 'Shri' is the deity of fortune.
	Vedic literature has described the expansive form of Shri or Lakshmi as the deity who 'enriches (shrimant)' by endowing with prosperity, wealth, health and longevity, progeny and continuation of the family tree, abundant food grain, servants, well-equipped servitors, etc.
	The book in Her hand symbolizes the Vedas, that is, spiritual knowledge.
	Meaning of the lotus and rising Sun: 'An indepth meaning has been attached to the blossoming of the lotus with the touch of the rising Sun. The sun is the representative of the dyu region [dyulok - a part of heaven (svargalok)], while the earth is his consort. The implied meaning of this is that the union of heaven and the earth gives birth to the universe as the fetus. In this way sages have associated the earth, that is, Shri, Who has the capacity to reproduce, with the lotus.'

    A diagram relating the various forms of Divine Energy, including Lakshmi, can be found here.

    [Reference taken from Volume 9B: Divine Energy (Shakti), compiled by Dr. Jayant B. Athavale and Dr. Mrs. Kunda Athavale, published by the Sanatan.]