Exhibit 5.1

June 30, 2023

Board of Directors

Crown Electrokinetics Corp.

1110 NE Circle Blvd.

Corvallis, OR 97330

Ladies and Gentlemen:

We have acted as counsel to Crown Electrokinetics Corp., a Delaware corporation (the “Company”), in connection with the Registration Statement on Form S-3 (the “Registration Statement”) filed by the Company on the date hereof with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), relating to the offering for resale of up to (i) an aggregate of 21,000,000 shares of common stock, par value $0.0001 per share (“Common Stock”), issuable upon the conversion of shares of the Company’s Series E Convertible Preferred Stock (“Series E Preferred Stock”); (ii) an aggregate of 35,527,740 shares of Common Stock issuable upon the conversion of shares of the Company’s Series F Convertible Preferred Stock (the “Series F Preferred Stock”); (iii) an aggregate of 23,902,602 shares of Common Stock issuable upon the conversion of shares of the Company’s Series F-1 Convertible Preferred Stock (the “Series F-1 Preferred Stock”); (iv) an aggregate of 7,496,749 shares of Common Stock issuable upon the conversion of shares of the Company’s Series F-2 Convertible Preferred Stock (the “Series F-2 Preferred Stock”); (v) an aggregate of 35,527,740 shares of Common Stock issuable upon exercise of certain outstanding warrants issued by the Company in connection with the Series F Preferred Stock (the “Series F Warrants”); (vi) an aggregate of 23,902,602 shares of Common Stock issuable upon exercise of certain outstanding warrants issued by the Company in connection with the Series F-1 Preferred Stock (the “Series F-2 Warrants”); (vii) an aggregate of 7,496,749 shares of Common Stock issuable upon exercise of certain outstanding warrants issued by the Company in connection with the Series F-2 Preferred Stock (the “Series F-2 Warrants” and together with the Series F Warrants and the Series F-1 Warrants, collectively, the “Warrants”); (viii) 1,903,429 shares of the Company’s Common Stock in connection with waiver agreements (the “Waiver Agreement and Amendments”) with holders of certain convertible promissory notes issued in 2022 to eliminate the minimum pricing covenant as it relates to Company’s At-The-Market facility (the “Waiver Agreement Shares”); (ix) 14,710,000 shares of the Company’s Common Stock in connection with extensions of the maturity date of certain senior secured notes issued on June 3, 2023 (the “January Notes”, and such shares, the “January Note Extension Shares”); (x) 2,000,000 shares of the Company’s Common Stock in connection with extensions of the maturity date of certain secured promissory notes under a Line of Credit Agreement with a lender (the “Line of Credit”, and such shares, the “Line of Credit Extension Shares”); and (xi) 7,413,622 shares of the Company’s Common Stock in connection with certain secured demand promissory notes issued between May 17, 2023 and May 30, 2023 (the “Demand Notes”, and such shares, the “Demand Note Shares”), for the account of the selling stockholders identified in the Registration Statement (the “Selling Stockholders”). This opinion letter is furnished to you at your request to enable you to fulfill the requirements of Item 601(b)(5) of Regulation S-K, 17 C.F.R. § 229.601(b)(5), in connection with the Registration Statement.

In our capacity as corporate counsel to the Company and for the purposes of this opinion, we have examined originals, or copies certified or otherwise identified to our satisfaction, of the following documents:

Crown Electrokinetics Corp.

June 30, 2023

Page 2

In rendering the opinion expressed below, we have assumed without verification the genuineness of all signatures, the legal capacity of natural persons, the authenticity of all documents submitted to us as originals, the conformity to the originals of all documents submitted to us as copies and the authenticity of the originals of such copies, and the due authorization, execution and delivery of all documents by all parties and the validity, binding effect and enforceability thereof (other than the authorization, execution and delivery of documents by the Company and the validity, binding effect and enforceability thereof upon the Company). In addition, we have assumed and not verified the accuracy as to the factual matters of each document we have reviewed and the accuracy of, and each applicable party’s full compliance with, any representations and warranties contained therein. As to questions of fact material to this opinion, we have, to the extent deemed appropriate, relied upon certain representations of certain officers of the Company. Accordingly, we are relying upon (without any independent investigation thereof) the truth and accuracy of the statements, covenants, representations and warranties set forth in the documents we have reviewed.

Crown Electrokinetics Corp.

June 30, 2023

Page 3

Based upon the foregoing and subject to the assumptions, exceptions, limitations and qualifications set forth herein, we are of the opinion that:

Our opinion is limited to applicable statutory provisions of the Delaware General Corporation Law and the reported judicial decisions interpreting those laws, and federal laws of the United States of America to the extent referred to specifically herein. We are generally familiar with the Delaware General Corporation Law as currently in effect and the judicial decisions thereunder and have made such inquiries and review of matters of fact and law as we determined necessary to render the opinions contained herein. We assume no obligation to revise or supplement this opinion letter in the event of future changes in such laws or the interpretations thereof or such facts. We express no opinion regarding the Securities Act, or any other federal or state laws or regulations.

This opinion letter is issued as of the date hereof and is necessarily limited to laws now in effect and facts and circumstances presently existing and brought to our attention. We assume no obligation to supplement this opinion letter if any applicable laws change after the date hereof, or if we become aware of any facts or circumstances that now exist or that occur or arise in the future and may change the opinions expressed herein after the date hereof.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Registration Statement and to the use of our name under the caption “Legal Matters” in the Registration Statement and the prospectus that forms a part thereof. In giving the foregoing consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act, or the rules and regulations of the Commission.