While ibn Kathir in his tafsir says that al-Abras الأبرص is known.
And made some details about the interpretation of al-Akmah الأكمه:
(And I heal him who is Akmah) meaning, 'a person who was born blind,' which perfects this miracle and makes the challenge more daring.
﴿وَالاٌّبْرَصَ﴾
(And the leper) which is a known disease, (Source: qtafsir)
The authors of qtafsir seem to support the view that al-Baras is leprosy and they didn't quote the details made by ibn Kathir (like the statement saying they are those who see by day and can't see by night and the opposite view).
While the commonly known -at least in Moroccan Arabic the term is well known- is that it refers to vitiligo.
As described and interpretd by imam al-Qurtobi in his tafsir:
والبرص معروف وهو بياض يعتري الجلد
where he is explaining that al-Baras is a diseas that shows up as white surfaces on the human skin. This was also quoted by ibn 'Ashur in his at-Tahrir wa-Tanwir and al-Baghawi supported this -in his tafsir- calling it وضح (which is what al-Qurtobi described) most other tafssir books detailed on the meaning(s) of al-Akmah and left al-Abras out as it seems to have been known (like ar-Razi in his at-Tafsir al-Kabir, az-Zamakhsari in his al-Kashaf and as said earlier ibn Kathir in his tafsir who said it is a known desease).
Note that the description made by al-Qurtobi also describes symptoms of leprosy - as mentioned by @Uma in a comment- therefore both meanings may apply as long as we have no better confirmation
