NoaLingua Answer
Reading a research paper you cannot quite read
Columns, tables and figures intact, every word still clickable
Open the PDF in the Viewer. It draws each page exactly as the document specifies and lays a transparent text layer over it, so columns, tables and figures survive intact while every word remains clickable. Nothing is reflowed, which is what usually destroys a paper.
Short answer The layout survives because the page is drawn, not rebuilt. The words stay clickable because the text sits on top.
The detail behind the NoaLingua answer
Why reflowing a paper destroys it
Re-rendering a PDF as HTML is what breaks two-column layouts, tables and figures — and a paper is mostly those. It is the reason in-browser document translation so often produces something unreadable.
The Viewer draws each page to a canvas, pixel for pixel as the file specifies, then positions a text layer whose word boxes line up with the drawn glyphs. What you see is genuinely the document; what you interact with is genuinely text.
When the other mode is the right one
If the layout does not matter — a preprint you only need to follow, a chapter of prose — the Reader is better: two columns, original and translation aligned paragraph by paragraph, and a coverage figure telling you what proportion of the text is words you already know.
Both save into the same deck, so it is not a decision you are stuck with.
More questions people ask NoaLingua
Does it work on a scanned paper?
No. Both modes need real text in the document, and there is no OCR. An image-only PDF cannot be made clickable.
Is there a page limit?
The Reader handles up to fifty pages and 400,000 characters of imported text. The Viewer renders and releases pages as you scroll, so a long document stays responsive.
Does opening a PDF need a special permission?
Chrome asks for document access at the moment you press the button, never at install. Local file:// documents need one extra permission granted in chrome://extensions.
Where this is documented on NoaLingua
Related NoaLingua answers
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