Поле зрения и межзрачковое расстояние нужно проверить.

Поле зрения is a fixed noun phrase meaning field of vision or visual field.

• поле = field
• зрения = of vision / of sight

Here, зрения is in the genitive singular. Russian often uses this structure where one noun modifies another:

• поле зрения = field of vision
• центр города = center of the city
• чашка чая = cup of tea

So зрения is not a separate main part of the sentence; it depends on поле.

They are functioning as the things that need to be checked, so logically they are the direct objects of проверить.

That means they are in the accusative case. However, for these particular words, the accusative looks exactly like the nominative:

• поле — nominative singular / accusative singular
• расстояние — nominative singular / accusative singular

So even though they look like nominative forms, in this sentence they are understood as accusative because they are the objects of проверить.

Because нужно here is not a normal verb agreeing with a subject. It is an impersonal predicative word meaning something like it is necessary or one needs to.

So it does not change to match the number of the nouns that follow or precede it.

Compare:

• Нужно проверить поле зрения. = It is necessary to check the visual field.
• Нужно проверить поле зрения и межзрачковое расстояние. = It is necessary to check the visual field and the interpupillary distance.

Even with two items, нужно stays the same.

This is a very common Russian structure:

• нужно + infinitive

It means it is necessary to do something.

So:

• нужно проверить = it is necessary to check / needs to be checked

There is no personal subject like I, you, or they in the sentence. The structure is impersonal.

Other examples:

• Нужно подождать. = It is necessary to wait.
• Нужно купить билет. = You need to buy a ticket.

Проверить is the perfective infinitive, which usually means checking something as a completed action or single task.

In this sentence, the idea is:

• these things need to be checked

That sounds like a definite, completed check, so проверить is natural.

If you used проверять instead, it would sound more like an ongoing, repeated, or general process:

• нужно проверять = one needs to check regularly / should be checking

So:

• нужно проверить = need to check (now / as a complete action)
• нужно проверять = need to check habitually / repeatedly

Yes, absolutely. In fact, that word order is probably the more neutral one.

Compare:

• Нужно проверить поле зрения и межзрачковое расстояние.
• Поле зрения и межзрачковое расстояние нужно проверить.

Both are correct.

The version with the objects first puts a little more focus on what needs checking. Russian word order is flexible, and moving parts of the sentence can change emphasis rather than basic meaning.

Межзрачковое means interpupillary — literally something like between-the-pupils.

It is an adjective modifying расстояние (distance), so it has to agree with it in gender, number, and case.

Since расстояние is:

• neuter
• singular
• here accusative singular (same form as nominative)

the adjective is also:

• neuter
• singular

That is why the ending is -ое:

• межзрачковое расстояние

If the noun were different, the adjective would change too:

• межзрачковый ... for masculine
• межзрачковая ... for feminine
• межзрачковые ... for plural

Yes, it is a standard technical or medical/optical term, especially in contexts like:

• eye exams
• glasses fitting
• optics
• VR headsets

It means interpupillary distance (IPD).

A learner does not need to break it apart every time, because it functions as one established term.

Because поле зрения and межзрачковое расстояние are simply two coordinated items joined by и (and).

Russian does not put a comma before и when it connects two items in a simple list or two homogeneous parts of the sentence:

• мама и папа
• чай и кофе
• поле зрения и межзрачковое расстояние

A comma would only appear in more complex situations, not in this simple coordination.

Yes. Надо проверить поле зрения и межзрачковое расстояние is also correct.

Both надо and нужно can mean need to / it is necessary to. In many contexts they are very close.

A rough difference:

• надо often sounds a bit more conversational
• нужно can sound a bit more neutral or slightly more formal

But in many real-life situations, either one would work.

Yes, the sentence leaves the doer unspecified. That is very common in Russian.

Depending on context, it could mean:

• you need to check
• we need to check
• someone needs to check
• it needs to be checked

Russian often uses impersonal structures when the exact subject is not important or is obvious from context.

So the sentence focuses on the necessity of the action, not on who will do it.

Because Russian has no articles.

So a phrase like:

• поле зрения

can mean:

• the field of vision
• a field of vision

depending on context.

The same is true for:

• межзрачковое расстояние = the interpupillary distance / an interpupillary distance

English needs articles; Russian does not. You understand definiteness from context instead.