EXHIBIT 5.1

                          OPINION OF HELLER EHRMAN LLP


April 6, 2006


Alpha Innotech Corp.
2401 Merced Drive
San Leandro, CA 94577

                       REGISTRATION STATEMENT ON FORM S-8

         Ladies and Gentlemen:

         We  have  examined  the   Registration   Statement  on  Form  S-8  (the
"REGISTRATION  STATEMENT")  filed  by  you  with  the  Securities  and  Exchange
Commission  (the   "COMMISSION")  on  April  6,  2006  in  connection  with  the
registration under the Securities Act of 1933, as amended, of a total of 854,311
shares of your Common Stock (the  "SHARES"),  which  reserved for issuance under
the Amended and  Restated  1999 Stock Option  Plan,  (the "1999 Plan),  the 2001
Milestone  Stock Option Plan (the "Bonus  Plan"),  and the  Non-Qualified  Stock
Option  Agreement  dated as of December 20, 2005 (the "NQO",  together  with the
1999 Plan and the Bonus Plan referred to as the "Plans").  Such number  consists
of (i) 434,305 shares  available for issuance under the 1999 Plan;  (ii) 120,006
shares  reserved under the Bonus Plan, and (iii) 300,000 shares reserved for the
NQO.

         In connection  with this opinion,  we have assumed the  authenticity of
all  records,  documents  and  instruments  submitted  to us as  originals,  the
genuineness of all  signatures,  the legal  capacity of natural  persons and the
conformity to the originals of all records,  documents and instruments submitted
to us as copies.  We have  based our  opinion  upon our review of the  following
records, documents and instruments:

         (a)      The Amended and Restated  Certificate of  Incorporation of the
Company, as amended to date, certified by the Secretary of State of the State of
Delaware as of April 5, 2006 and certified to us by an officer of the Company as
being complete and in full force and effect as of the date of this opinion;

         (b)      The Bylaws of the Company, as amended to date, certified to us
by an officer of the Company as being  complete  and in full force and effect as
of the date of this opinion;

         (c)      A  Certificate  of an officer  of the  Company  (i)  attaching
records  certified to us as constituting  all records of proceedings and actions
of the Board of  Directors  and  stockholders  of the  Company  relating  to the
adoption  and  approval of the Plans and the  Registration  Statement,  and (ii)
certifying as to certain factual matters;

         (d)      A Certificate of American Stock Transfer & Trust Company,  the
transfer agent of the Company, certifying as to the number of outstanding shares
of common stock of the Company;

         (e)      The Registration Statement; and

         (f)      The Plans.

         This  opinion is limited to the  federal  laws of the United  States of
America and the General  Corporation  Law of the State of Delaware.  We disclaim
any opinion as to any other statute, rule, regulation, ordinance, order or other
promulgation  of any other  jurisdiction  or any regional or local  governmental
body or as to any related judicial or administrative opinion.

         Based upon the foregoing and our  examination  of such questions of law
as we have deemed necessary or appropriate for the purpose of this opinion,  and
assuming  that (i) the  Registration  Statement  becomes and  remains  effective
during the period when the Shares are offered,  issued and sold, (ii) the Shares
to be sold are issued in accordance with the terms of the applicable Plan, (iii)
the  Company  receives  the full  consideration  for the Shares as





stated in the applicable Plan, (iv) the per share  consideration  for each Share
includes payment of cash or other lawful consideration at least equal to the par
value of the Company's Common Stock, and (v) all applicable  securities laws are
complied  with,  it is our opinion that the Shares  covered by the  Registration
Statement,  when issued and sold by the Company,  after payment therefore in the
manner provided in the applicable Plan and the Registration  Statement,  will be
legally issued, fully paid and nonassessable.

         This  opinion is rendered to you in  connection  with the  Registration
Statement and is solely for your benefit. This opinion may not be relied upon by
you for any other purpose, or relied upon by any other person, firm, corporation
or other entity for any purpose,  without our prior written consent. We disclaim
any  obligation to advise you of any change of law that occurs,  or any facts of
which we may become aware, after the date of this opinion.

                                                      Very truly yours,

                                                      /s/ Heller Ehrman LLP
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                                                      Heller Ehrman LLP