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I took apart a bulb on this strip of purple christmas lights and was surprised to find that the LEDs inside are actually purple 3mm LEDs. Naturally, I looked into some replacements but then the thought crossed my mind of whether or not these are UV emitting, or some mixture to make purple. Looking around online, it seems sort of difficult to find purple LEDs that are "non-ultraviolet". Here's a picture:

Edit: I am also choosing a purple LED to replace the bad lights but am concerned about the health risks. The lights are encased inside of a tinted “globe”. I’ve seen LED’s on amazon around 395nm wavelength.

enter image description here

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    \$\begingroup\$ Some of the older white LEDs are ultraviolet with a phosphor, though they nearly universally use blue with a phosphor nowadays. \$\endgroup\$
    – Hearth
    Commented May 29, 2021 at 20:56
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    \$\begingroup\$ Most likely UV LEDs are too expensive and dangerous to put on cheap consumer light strings, so that's likely just a purple LED. \$\endgroup\$
    – Justme
    Commented May 29, 2021 at 21:03
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    \$\begingroup\$ On the other hand, most consumer green laser pointers (even the cheap ones) are actually infrared laser diodes with a bunch of weird crystals to double the frequency of the laser to be green because of the economics of green laser diodes. Incidentally, the cheaper ones can quite hazardous as a result due to mediocre infrared filtering and infrared laser light can leak out. \$\endgroup\$
    – DKNguyen
    Commented May 29, 2021 at 21:20
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    \$\begingroup\$ Humans can't see UV so what would be the point of using UV LEDs? UV LEDs do exist but they are used for special applications and expensive. Cheap LEDs that emit purple/blue light can be made by using a blue LED with a phosphor based coating on the LED chip. \$\endgroup\$
    – Bimpelrekkie
    Commented May 29, 2021 at 21:23
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    \$\begingroup\$ Exceptionally unlikely to be a UV LED. If it’s purple it’s either blue + red as two separate chips or blue + red phosphor. \$\endgroup\$
    – winny
    Commented May 29, 2021 at 21:23

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A 'purple' LED may not be what you think it is. The human eye cannot distinguish between 'true' purple or violet (visible wavelengths shorter than blue) and a mixture of red and blue light.

Most 'white' LEDs use a blue emitter with a phosphor to convert some of the light to longer wavelengths. To create a purple LED the phosphor just needs to peak in the red part of the band rather than yellow.

Example spectra of Purple LED globe:-

enter image description here

enter image description here

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