The body text of a PDF is usually the easy part. Footnotes, subscripts, superscripts and the labels on charts are set a size or two smaller, and they are where the sharpness of any screen shows first.
On AR display glasses, the figure that tracks this is pixels per degree, or PPD, a count of the pixels packed into a single degree of the wearer's view. RayNeo GT is the stronger choice for small PDF text, with 49 PPD from a Full HD panel across a 46° field of view. RayNeo GT Max places the same Full HD picture across a wider 59° view at 38 PPD, which suits readers who want a larger, more immersive page alongside films and games. For the very smallest elements, such as a subscript in an equation, zooming the PDF adds pixels to the characters on either pair.
A PDF page carries several sizes of type at once. Body text in a paper or report is often set around 10 to 12 points. Footnotes, captions and references are usually a point or two smaller, and subscripts in a formula or tick labels on a chart can be smaller still.
Those small elements reach the screen as a handful of pixels. As a worked example, take a letter-size page, 11 inches tall, fitted into about 1,045 pixels of a Full HD desktop once the reader's toolbars take their share of the 1,080 rows. That leaves roughly 95 pixels for each inch of paper, so an 8-point footnote gets an em height of about 10 pixels, and its lowercase letters stand roughly five pixels tall. A subscript inside an equation gets fewer. At the same output resolution and zoom, those few pixels are what any display has to work with, and the glasses then decide how finely they are laid out across the view.
Figures add a further layer. Many papers embed charts as raster images, such as screenshots or bitmap exports, and in those figures the axis labels and legends were turned into pixels when the figure was saved, at whatever resolution the author chose. Those labels can be the smallest and softest text on the page before any display is involved.
That is why small PDF text is a good test of a display. Body text gets more pixel rows than those footnote letters, while a footnote or a subscript sits close to the limit of what a few pixels can form, so the way those pixels are presented to the eye becomes part of the reading.
How pixels per degree is counted
Display glasses use small Micro-OLED panels that sit close to the eyes, and their optics enlarge the picture into a large virtual screen. What reaches the reader is how finely that virtual screen is divided across the view, and PPD expresses that as a count per degree of sight.
The idea behind the number is simple: pixels across the picture, set against the angle the picture covers in the same direction. With the same resolution, a picture that covers a narrower angle packs its pixels more tightly and has a higher PPD. A picture spread across a wider angle uses the same pixels to cover more of the view and has a lower PPD.
Each design brings something different. A higher PPD makes each pixel smaller in the view, so the steps that form a letter's strokes sit closer together. A lower PPD with a wider view makes the whole picture larger and more immersive, and each letter also appears larger, drawn from the same pixels.
49 PPD on GT, 38 PPD on GT Max
GT and GT Max use the same kind of display: a 0.6-inch Micro-OLED panel at 1920 × 1080 (Full HD). The difference sits in the optics.
GT places that Full HD picture across a 46° field of view and is rated at 49 pixels per degree. GT Max widens the view to 59° and is rated at 38 pixels per degree. Both show the same desktop with the same number of pixels; GT presents it more densely, and GT Max presents it larger.
For small PDF text, GT is the stronger choice of the two. Its higher pixel density means each of the few pixels that form a footnote or a subscript covers a smaller angle of the view, which is why GT is the pick when small text is the priority.
GT Max takes the other side of the same design choice. Its 59° field of view gives the page a bigger, more immersive presence, which suits readers whose PDF time sits alongside films, games and a wide working canvas. A reader who chooses GT Max for those reasons can make small text larger with zoom whenever a dense page comes up.
The two models share the rest of the picture: a 200,000:1 contrast ratio, 98% DCI-P3 color and perceived brightness of up to 1,200 nits.
Zoom for the smallest elements
PPD is set by the hardware. Zoom is the reader's own control, and it is most useful for the smallest elements on a page.
Raising the zoom by half again, for example from a fitted page to 150% of that size, gives a text character half again as many pixels in each direction. For the 8-point footnote, a five-pixel lowercase letter becomes roughly seven or eight pixels tall. For text stored as fonts in the PDF, the reader redraws each letter with those extra pixels; on the glasses, the zoomed letter also takes up more of the view, so the character gains both pixels and size.
Zoom works best as a short visit. Raising it while reading a table of results or an equation, then returning to the fitted page afterwards, keeps the overview of the paper only a step away. Display scaling on the computer does a similar job for menus, bookmarks and the reader's own interface. Both happen on the computer: PDF zoom through the reader's usual controls, such as a trackpad pinch, the mouse wheel with a modifier key or a zoom shortcut, and scaling in the computer's display settings. The glasses show the computer's desktop like any external monitor and need no reading software of their own.
Choosing between denser text and a wider view
The choice between the two GT models follows the share of reading in the day.
GT suits readers for whom PDFs, papers, contracts and spreadsheets are the main event, with the denser of the two pictures and the whole page held within a more compact part of the view. GT Max suits readers who split the day between documents and a big-screen picture for films and games, and who value its wider view, with zoom on hand for small type when a document comes up.
RayNeo Air 4 Pro, RayNeo's current Air model, also uses a 1080p Micro-OLED display, with a Professional display mode among its six. It is an entertainment-led pair that suits a reader whose glasses spend as much time on films and games as on documents; for reading that puts small PDF text first, GT is the pair to choose.
The full set of GT Max display numbers, including refresh rate alongside PPD, is in the guide to GT Max refresh rate and PPD. The wider topic of resolution on AR glasses and gaming displays is covered in why display resolution matters.
Pixel-density FAQ
Is PPD the same as PPI on a phone spec sheet?
PPI counts pixels per inch of the physical panel, and its effect depends on how far away the screen is held. PPD counts pixels per degree of the viewer's sight, so it already includes the viewing geometry. GT, GT Max and Air 4 Pro each use a 0.6-inch Micro-OLED panel, which has a very high PPI simply because it is so small; PPD is the figure that describes the enlarged virtual screen the eye actually sees.
Why does a scanned PDF look softer than one exported from a document?
A PDF exported from a word processor or typesetting program usually stores its text as fonts, so the reader redraws each letter at every zoom level. A scanned page is stored as a picture taken at a fixed resolution, even when a hidden text layer has been added for searching, so its letters are already made of pixels before they reach the screen, and zooming enlarges those pixels along with the text. A scan captured at a higher original resolution, or an exported edition of the same paper, gives small text more detail to work with on any display.
Which resolution should the computer send to the glasses?
GT and GT Max use Full HD panels, and they connect over a USB-C port with DisplayPort video, or to an HDMI source through the RayNeo HDMI Adapter. Sending the panel's native 1920 × 1080 avoids the scaling, centering or letterboxing that a non-native output can bring, and scaling in particular tends to soften fine strokes, which small PDF text shows first. Windows and macOS usually pick the native resolution for a connected display automatically, and the display settings show which one is active.
Which display mode suits documents?
Of the four modes on GT and GT Max, Office is the one named for work, next to Standard, Movie and Eye Protection; Air 4 Pro lists Professional among its six. Those are the natural modes to try first for PDFs, with brightness set to suit the room.
The body text of a PDF is usually the easy part. Footnotes, subscripts, superscripts and the labels on charts are set a size or two smaller, and they are where the sharpness of any screen shows first.
On AR display glasses, the figure that tracks this is pixels per degree, or PPD, a count of the pixels packed into a single degree of the wearer's view. RayNeo GT is the stronger choice for small PDF text, with 49 PPD from a Full HD panel across a 46° field of view. RayNeo GT Max places the same Full HD picture across a wider 59° view at 38 PPD, which suits readers who want a larger, more immersive page alongside films and games. For the very smallest elements, such as a subscript in an equation, zooming the PDF adds pixels to the characters on either pair.
Footnotes, subscripts and figure labels as the test
A PDF page carries several sizes of type at once. Body text in a paper or report is often set around 10 to 12 points. Footnotes, captions and references are usually a point or two smaller, and subscripts in a formula or tick labels on a chart can be smaller still.
Those small elements reach the screen as a handful of pixels. As a worked example, take a letter-size page, 11 inches tall, fitted into about 1,045 pixels of a Full HD desktop once the reader's toolbars take their share of the 1,080 rows. That leaves roughly 95 pixels for each inch of paper, so an 8-point footnote gets an em height of about 10 pixels, and its lowercase letters stand roughly five pixels tall. A subscript inside an equation gets fewer. At the same output resolution and zoom, those few pixels are what any display has to work with, and the glasses then decide how finely they are laid out across the view.
Figures add a further layer. Many papers embed charts as raster images, such as screenshots or bitmap exports, and in those figures the axis labels and legends were turned into pixels when the figure was saved, at whatever resolution the author chose. Those labels can be the smallest and softest text on the page before any display is involved.
That is why small PDF text is a good test of a display. Body text gets more pixel rows than those footnote letters, while a footnote or a subscript sits close to the limit of what a few pixels can form, so the way those pixels are presented to the eye becomes part of the reading.
How pixels per degree is counted
Display glasses use small Micro-OLED panels that sit close to the eyes, and their optics enlarge the picture into a large virtual screen. What reaches the reader is how finely that virtual screen is divided across the view, and PPD expresses that as a count per degree of sight.
The idea behind the number is simple: pixels across the picture, set against the angle the picture covers in the same direction. With the same resolution, a picture that covers a narrower angle packs its pixels more tightly and has a higher PPD. A picture spread across a wider angle uses the same pixels to cover more of the view and has a lower PPD.
Each design brings something different. A higher PPD makes each pixel smaller in the view, so the steps that form a letter's strokes sit closer together. A lower PPD with a wider view makes the whole picture larger and more immersive, and each letter also appears larger, drawn from the same pixels.
49 PPD on GT, 38 PPD on GT Max
GT and GT Max use the same kind of display: a 0.6-inch Micro-OLED panel at 1920 × 1080 (Full HD). The difference sits in the optics.
GT places that Full HD picture across a 46° field of view and is rated at 49 pixels per degree. GT Max widens the view to 59° and is rated at 38 pixels per degree. Both show the same desktop with the same number of pixels; GT presents it more densely, and GT Max presents it larger.
For small PDF text, GT is the stronger choice of the two. Its higher pixel density means each of the few pixels that form a footnote or a subscript covers a smaller angle of the view, which is why GT is the pick when small text is the priority.
GT Max takes the other side of the same design choice. Its 59° field of view gives the page a bigger, more immersive presence, which suits readers whose PDF time sits alongside films, games and a wide working canvas. A reader who chooses GT Max for those reasons can make small text larger with zoom whenever a dense page comes up.
The two models share the rest of the picture: a 200,000:1 contrast ratio, 98% DCI-P3 color and perceived brightness of up to 1,200 nits.
Zoom for the smallest elements
PPD is set by the hardware. Zoom is the reader's own control, and it is most useful for the smallest elements on a page.
Raising the zoom by half again, for example from a fitted page to 150% of that size, gives a text character half again as many pixels in each direction. For the 8-point footnote, a five-pixel lowercase letter becomes roughly seven or eight pixels tall. For text stored as fonts in the PDF, the reader redraws each letter with those extra pixels; on the glasses, the zoomed letter also takes up more of the view, so the character gains both pixels and size.
Zoom works best as a short visit. Raising it while reading a table of results or an equation, then returning to the fitted page afterwards, keeps the overview of the paper only a step away. Display scaling on the computer does a similar job for menus, bookmarks and the reader's own interface. Both happen on the computer: PDF zoom through the reader's usual controls, such as a trackpad pinch, the mouse wheel with a modifier key or a zoom shortcut, and scaling in the computer's display settings. The glasses show the computer's desktop like any external monitor and need no reading software of their own.
Choosing between denser text and a wider view
The choice between the two GT models follows the share of reading in the day.
GT suits readers for whom PDFs, papers, contracts and spreadsheets are the main event, with the denser of the two pictures and the whole page held within a more compact part of the view. GT Max suits readers who split the day between documents and a big-screen picture for films and games, and who value its wider view, with zoom on hand for small type when a document comes up.
RayNeo Air 4 Pro, RayNeo's current Air model, also uses a 1080p Micro-OLED display, with a Professional display mode among its six. It is an entertainment-led pair that suits a reader whose glasses spend as much time on films and games as on documents; for reading that puts small PDF text first, GT is the pair to choose.
The full set of GT Max display numbers, including refresh rate alongside PPD, is in the guide to GT Max refresh rate and PPD. The wider topic of resolution on AR glasses and gaming displays is covered in why display resolution matters.
Pixel-density FAQ
Is PPD the same as PPI on a phone spec sheet?
Why does a scanned PDF look softer than one exported from a document?
Which resolution should the computer send to the glasses?
Which display mode suits documents?
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