Exhibit 10.31

AMENDMENT NUMBER THREE TO LOAN AND
SECURITY AGREEMENT AND WAIVER

This Amendment Number Three to Loan and Security Agreement and Waiver ("Third Amendment") is entered into as of December 11, 2002, by and between FOOTHILL
CAPITAL CORPORATION,a California corporation ("Foothill"), andEVANS & SUTHERLAND COMPUTER
CORPORATION, a Utah corporation ("Borrower"), in light of the following:

A.    Borrower
and Foothill have previously entered into that certain Loan and Security Agreement, dated as of December 14, 2000;

B.    On
or about June 19, 2001, Borrower and Foothill entered into that certain amending Letter Agreement, whereby certain terms and conditions of the Agreement were
temporarily amended;

C.    On
or about February 22, 2002, Borrower and Foothill entered into that certain Amendment Number One to Loan and Security Agreement whereby certain terms and
conditions of the Agreement were amended;

D.    On
or about August 14, 2002, Borrower and Foothill entered into that certain Amendment Number Two to Loan and Security Agreement whereby certain terms and
conditions of the Agreement were further amended (the Loan Agreement, as amended by the letter agreement, the first amendment, and the second amendment, as referenced above, is hereinafter referred to
as the "Loan Agreement");

E.    Pursuant
to its terms, the Loan Agreement is set to expire on or about December 14, 2002, and Borrower has requested that the terms be extended, and that certain
other terms and conditions be amended; and

F.    Borrower
and Foothill desire to extend the term of the Loan Agreement and to further amend the Loan Agreement as provided for and on the conditions herein.

NOW, THEREFORE,Borrower and Foothill hereby amend and supplement the Agreement as follows:

1.DEFINITIONS.All initially capitalized terms used in this Second Amendment shall have
the meanings given to them in the Agreement unless specifically defined herein.

2.AMENDMENTS.



600 Komas Drive

$
4,617,000650 Komas Drive

$
2,793,000770 Komas Drive

$
1,559,000790 Komas Drive

$
241,000540 Arapeen Drive

$
1,331,000560 Arapeen Drive

$
2,973,000580 Arapeen Drive

$
2,086,000Electric Substation

$
651,000
"


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600 Komas Drive

$
7,978,000650 Komas Drive

$
4,826,000770 Komas Drive

$
2,694,000790 Komas Drive

$
416,000540 Arapeen Drive

$
2,301,000560 Arapeen Drive

$
5,137,000580 Arapeen Drive

$
3,605,000Electric Substation

$
1,124,000
"




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3.REPRESENTATIONS AND WARRANTIES.Borrower hereby affirms to Foothill that all of
Borrower's representations and warranties set forth in the Agreement are true, complete and accurate in all respects as of the date hereof.

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4.NO DEFAULTS.Borrower hereby affirms to Foothill that, other than Events of Default
having been expressly waived by Foothill in writing, no Event of Default has occurred and is continuing as of the date hereof.

5.CONDITION PRECEDENT.The effectiveness of this Second Amendment is expressly
conditioned upon the receipt by Foothill of an executed copy of this Second Amendment.

6.COSTS AND EXPENSES.Borrower shall pay to Foothill all of Foothill's
out-of-pocket costs and expenses (including, without limitation, the fees and expenses of its counsel, which counsel may include any local counsel deemed necessary, search
fees, filing and recording fees, documentation fees, appraisal fees, travel expenses, and other fees) arising in connection with the preparation, execution, and delivery of this Amendment and all
related documents.

7.LIMITED EFFECT.In the event of a conflict between the terms and provisions of this
Second Amendment and the terms and provisions of the Agreement, the terms and provisions of this Second Amendment shall govern. In all other respects, the Agreement, as amended and supplemented
hereby, shall remain in full force and effect.

8.COUNTERPARTS; EFFECTIVENESS.This Second Amendment may be executed in any number of
counterparts and by different parties on separate counterparts, each of which when so executed and delivered shall be deemed to be an original. All such counterparts, taken together, shall constitute
but one and the same Second Amendment. This Second Amendment shall become effective upon the execution of a counterpart of this Second Amendment by each of the parties hereto.

IN
WITNESS WHEREOF, the parties hereto have executed this Second Amendment as of the date first set forth above.

| |  | FOOTHILL CAPITAL CORPORATION,a California corporation
| |  | -----------------------------------------------------
| |  | By:                                                  
| |  | Title:                                               
| |  | EVANS & SUTHERLAND COMPUTER,a Utah corporation       
| |  | By:                                                  
| |  | Title:                                               

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