Consolidated Balance Sheets (USD $)	Oct. 31, 2011	Jul. 31, 2011
Assets
Cash and cash equivalents	$ 992,000	$ 1,794,000
Accounts receivable, net	119,000	50,000
Inventories, net	850,000	861,000
Prepaid expenses	189,000	100,000
Total current assets	2,150,000	2,805,000
Property, plant and equipment, net	357,000	426,000
Patents, net	1,908,000	1,917,000
Total assets	4,415,000	5,148,000
Liabilities and stockholders' equity
Accounts payable	1,025,000	677,000
Accrued liabilities	348,000	258,000
Total current liabilities	1,373,000	935,000
Deferred rent	2,000	6,000
Total liabilities	1,375,000	941,000
Commitments and contingencies
Stockholders' equity
Preferred stock, $.01 par value: 5,000,000 shares authorized, no shares issued	0	0
Common stock, $0.01 par value: 100,000,000 shares authorized 41,148,206 issued and outstanding at October 31, 2011, and 40,034,659 issued and outstanding at July 31, 2011	411,000	400,000
Additional paid-in capital	58,600,000	57,417,000
Accumulated deficit	(55,971,000)	(53,610,000)
Total stockholders' equity	3,040,000	4,207,000
Total liabilities and stockholders' equity	$ 4,415,000	$ 5,148,000