Is << noun + "for" + gerund >> a valid noun phrase construction to indicate purpose of the head noun in a normal sentence (i.e. not in a title)?

Question

The following two sentences are patentese (written in language used in a patent):

A display apparatus includes a display device for displaying an image.

The display apparatus may include an optical film for limiting reflection of external, ambient light.

In 'normal' general English, I would say that writing "to display" and "to limit" sounds more natural, where the "to" is short for "in order to", thus using the << noun + "to (in order to)" + infinitive >> noun phrase construction instead. Also, acceptable would be << noun + "for the purpose of" + gerund >>, but this is perhaps unnecessarily long-winded.

Doing a search online gives acceptable examples of the noun phrase construction << noun + "for" + gerund >> used in titles, for example:

A simple method for displaying the hydropathic character of a protein

Options for Limiting the Potential to Emit (PTE) of a Stationary Source Under Section 112 and Title V of the Clean Air Act (CAA)

For these titles (that are a noun phrase standalone construction without a verb), the << noun + "for" + gerund >> construction is valid and sounds natural to me, but what about if we change these into a normal sentence including verbs, for example:

We describe a simple method for displaying the hydropathic character of a protein.

There are options for limiting the potential to emit (PTE) of a stationary source under Section 112 and Title V of the Clean Air Act (CAA).

The latter quoted sentence sounds fine, but the former sounds a bit unnatural to me due to the << noun + "for" + gerund >> construction within.

[[My original question, referred to these two quotes of titles with this unintentionally misleading comment: But these seem to be missing a verb, if what is intended is a normal complete sentence.]]

So, I'd like to ask: Are the first two sentences quoted above acceptable? Do they sound natural? If not, why not and what are the best alternatives?

Answer 1

The first two sentence are good for displaying your question. However, you use display three times (if we include displaying), which is repetitious. How about "a special device for displaying ..."?

There is a difference between to display and for displaying, and you have the right one to my ear. Use 'to act' in such settings to mean a direct cause and effect, not just an option:

I work to get paid. That is the reason I work.

Use for acting to mean you are offering an option that could be used for that purpose:

I have a rag for cleaning my desk. Remind me to do just that—perhaps next year.

Answer 2

They're not complete sentences by themselves, and titles seldom are; I definitely don't think I've ever seen a research paper with the title as a full sentence (think of how you'd label a list: "Items for school", "Places to visit", "Required for playing piano", etc.). Even modifying it to use an infinitive doesn't lead to a perfect sentence. It's either missing a subject or a predicate, depending on how you look at it.

It definitely sounds natural to me, since for is very commonly used to imply purpose or intent. And IMHO it definitely sounds less clumsy and awkward than "in order to" or "for the purpose of"; just because you can expand a single word into a long phrase doesn't mean it's correct to do so.