The text is not sharp on HP M22F 1080P External Monitor.

Text on your HP M22F monitor will never be anywhere near as sharp as the text on your M4 MacBook Air's built-in screen. There is no way to "fix" that.

The HP M22F is a 21.5" monitor with a resolution of 1920x1080 pixels. (See HP's data sheet.) That works out to a pixel density of about 102.5 pixels per inch. A 13" M4 MacBook Air has a 13.6" screen with a resolution of 2560x1664 pixels. That works out to a pixel density of about 224 pixels per inch.

So the MacBook Air's screen has about 2.2x as many pixels per inch, or 4.8x as many pixels per square inch, as the HP M22F's screen. That means that when drawing text strings or filling in photo areas of a given physical size, the MacBook Air's screen's greater resolution lets the Mac draw letter shapes more accurately and fill in photo areas in more detail.

asantamzid wrote:

Thanks so on the 4k monitor the text will look fully sharp?

It depends on the size of the 4K monitor. Pixel density depends both on resolution and on monitor size. A UHD 4K monitor has a diagonal measurement of about 4405.81 pixels. So,

• A 24" 4K monitor has a pixel density of 183.6 PPI
• A 27" 4K monitor has a pixel density of 163.2 PPI
• A 32" 4K monitor has a pixel density of 137.7 PPI
• etc.

If you were running a 24" 4K monitor in "looks like 1920x1080" mode, things would be sized as if the monitor had a resolution of 1920x1080 pixels, but the Mac would draw at a 3840x2160 level of detail. So you'd have the same workspace as on the HP M22F, but with sharper text.

I know of only a couple of standalone 24" 4K monitors. One (LG 24UD58-B) is affordable – but its specifications say nothing about how well it covers standard color gamut (sRGB). The other (the ASUS ProArt Display PA24US) has a ton of advanced color accuracy features, but goes for $1299. It seems to be intended for people who make their living from photo and video work. Maybe there are other 24" 4K displays out there "in the middle", but so far I haven't seen them. (The 24" M4 iMac has a very nice built-in 23.5" 4.5K Retina display. Unfortunately, the iMac display is only for the use of the iMac, and cannot act as a hardware monitor for any other computer.)

27" 5K monitors are nice – but they're expensive. Apple's Studio Display costs $1599+.

There are a bunch of 27" 4K monitors at all feature and price levels.

Your connection to the display and the cable used can greatly affect the sharpness of the display, especially at 1080P.

I suggest getting a certified USB-C to HDMI cable and no longer than one meter in length. The is no guarantee of the transmission quality of a cable that is not certified regardless of what the manufacturer claims. A certified cable will have the HDMI logo on the box as well as on the cable.

FWIW, this is the cable I use on my 4K, 27", LG HD display ad the text is sharp even when set at a 3003x1692 display size (@ 4K display size things are too small). At 2560x1440 it is even sharper.

certified cable

FYI, this is generally what the HDMI certification logo looks like: