A quick search turned up the following. The list is non-exhaustive and wasn't vetted in detail.

2017: Aging Retinal Function Is Improved by Near Infrared Light (670 Nm) ...

"Our data suggest, 670 nm light can significantly improve aged retinal function"

https://pubmed.ncbi.nlm.nih.gov/28129566/

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2016: Red Light of the Visual Spectrum Attenuates Cell Death in Culture and Retinal Ganglion Cell Death in Situ

" Low, non-toxic levels of red light focussed on the retina for a short period of time are sufficient to attenuate an insult of raised IOP to the rat retina"

https://pubmed.ncbi.nlm.nih.gov/26928988/

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2015: Mitochondrial Decline Precedes Phenotype Development in the Complement Factor H Mouse Model of Retinal Degeneration but Can Be Corrected by Near Infrared Light

"we provide evidence for a mitochondrial basis for this disease in mice and correct this with simple light exposure known to improve mitochondrial function"

https://pubmed.ncbi.nlm.nih.gov/26149919/

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2013: 670 nm light mitigates oxygen-induced degeneration in C57BL/6J mouse retina

"These results suggest that pretreatment with 670 nm light may provide stability to photoreceptors"

https://pubmed.ncbi.nlm.nih.gov/24134095/

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2013: Low-Intensity Far-Red Light Inhibits Early Lesions That Contribute to Diabetic Retinopathy: In Vivo and In Vitro

"Daily 670-nm PBM treatment resulted in significant inhibition in the diabetes-induced death of retinal ganglion cells"

https://pubmed.ncbi.nlm.nih.gov/23557732/

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2013: Paranode Abnormalities and Oxidative Stress in Optic Nerve Vulnerable to Secondary Degeneration: Modulation by 670 Nm Light Treatment

"Light at a wavelength of 670 nm may serve as a therapeutic intervention for treatment of secondary degeneration following neurotrauma"

https://pubmed.ncbi.nlm.nih.gov/23840470/

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2012: Age-related Retinal Inflammation Is Reduced by 670 Nm Light via Increased Mitochondrial Membrane Potential

"670 nm light [...] significantly increased mitochondrial membrane polarization and significantly reduced macrophage numbers and tumor necrosis factor-alpha levels"

https://pubmed.ncbi.nlm.nih.gov/22595370/

And this site includes an interesting chart of effective light frequencies:

"This chart pulled from the Joovv site shows that one of the receptors of light energy in our body, Cytochrome C Oxidase, absorbs many more photons at certain wavelengths."

https://primalhacker.com/blogs/learn/red-light-photobiomodul...

Thanks for posting, I appreciate it. This effect is quite interesting.