I thought I posted a reply, but it did not appear, so I will summarize.
I do not know much about Persian/Sufi latiafs; I was drawing from Hindu Theosophy, or just Sanatana Dharma's
Yoga philosophy. In it 3rd-eye/ajna chakra may be the seat of holy-/middle-spirit/oversoul/paramatma/chu/jeshida/monad (a.k.a. one's personal 'Father',) but crown/sahasrara chakra is more the seat of deity-/high-spirit/Word/Shabdhabrahman/Amen/Ha'shem/Logos. The pineal gland (associated with sahasrara; pituitary is associated with ajna) has optic nerves and is in about the place of ajna. When Shakti/Shekhinah induction pierces ajna, it illuminates the inner field of vision (which is usually blinded in darkness ;) clairvoyance.
Matthew 6:22 describes this, and it briefly happened to me, and once I saw light above my eyes (halo?) and when I drew energy down into my ajna, my friend (she did not know what I was doing) said 'I saw light come down to your 3rd eye.' The latter two events are not necessarily as incandescent (about 'inner light') as the 1st former.
Of course light (the following being a simpler statement about it without '[]' sections except 'changes') is [photon particles--non-material--of] force that change[s] into energy waves. I do not know if 'twas pranic/vital/ethereal, kamic/thymotic/astral, manasic/noetic/mental (etc., though I doubt 'twas anupadakan/monadic/oversoulful) clairvoyance. Though for some reason (or none) I describe the [latter] 2nd plane 'incandescent,' I did not mean I saw there, but only it influences enclosed lower consciousness. As for ethereal matter, it may also be viewable.
I know one method for viewing light or ethereal-matter, and I will describe methods that led to my Shakti-awakening. As described in the healing touch book
Hands of Light, if one sits/lays back under a clear sky and looks up at it mostly 'without focus,' one will soon see many tiny moving particles of light (which may also be partly matter as well as force and be called 'vitality globules' in Theosophy.) Also if one moves, or perhaps does not move, the back in a way they usually do not do, such as keeping it perfectly aligned for a long time (esp. looking at the sky,) or doing a handstand or flip, they will likely see light particles. I suppose from exercise it is prana/ankh/coach-ha-guf/bios/vital-ether, and in the sky it is natures own force/energy. This is not risky, but may lead one to want to try the following.
Ashtanga Yoga described by Sri Pattabhi Jois (continual Hatha series) or his students (Beryl Birch, Lino Miele) and Ashtanga described by Patanjali--meditation-contemplation--is effective in a couple weeks (preferably after doing requirements longer such as veg[etari]anism and yogic or at least careful breathing) for pranotthana-shaktipat, but some philosophers call Hatha yoga black magic. One must at least balance confidence, virtue and restraint (being selflessness rather than self, but having good/lawful purpose[s] for one's ego) or become overwhelmed by the new consciousness (which also may cause much heat) and perhaps become unsure or bored of what to do, and maybe considered insane. St. John of The Cross describes most aspects of insanity in his mystical books, and another Carmelite had smoke/steam issuing from her chest when she died. However, one gets used to it, and after a few months of weekly Yoga & meditation-contemplation Kundalini-Shakti could pierce spinal chakras and 3rd-eye, but be aware of risks if without a teacher.
Sungazing (http://www.solarhealing.com,
http://www.suryayog.com) is said to awaken Shakti, but be aware of risks if accidentally looking in times of UV light (supposedly none at certain times, which is why it could be done) or when sun is covered like the moon would (not necessarily clouds, but who knows.)
Consuming ORME (http://groups.yahoo.com/search?query=ormes 'Ormes' (skeptical,)
http://www.subtleenergies.com/ormus/ (pseudoscientific, but leads to some scientific info)) is said to awaken Shakti, but be aware of the risks if one tries a pseudo-scientific mixture or does not purify their consciousness 1st.
I would say if one has enough reasoning to read
Isis Unveiled and
The Secret Doctrine (incl. the posthumous non-index vol. 3) and understand most or to otherwise be a Theosophist, one is ready to consider these methods with veg[etari]nism as for ethics/health and spiritual development. Note ORME may not be safe unless one is veg*n, and veganism is not safe without b12 and ω-acids. I guess I reconstructed my post: I did not mean to say so much but said other perhaps interesting things I had to say things about.