Talk:Lenticular lens

Holograms

Isn't it possible to use holograms as lenticular lenses? How? Trekphiler 17:26, 16 August 2007 (UTC)

The technology is different completely, but many people still confuse the two kinds of products.Bernard SOULIER (talk) 21:13, 9 December 2007 (UTC)

External links

Hi Guys,

The external links on this page are nothing short of advertisements, with the pages linked to offering lenticular printing services. Please can we have a discussion regarding this before blindly reinstating the pages. I h ave posted a discussion to a couple of anon pages. The pages in question do not comply with WP:LINK as far as i see.

Thanks User A1 01:09, 4 November 2007 (UTC)

I referred this issue to Wikipedia:Editor assistance/Requests#lenticular lens, and have followed advice there. Please comment before adding links to this page, such that only links of good quality are included in the article. Thanks User A1 10:54, 4 November 2007 (UTC)

This discussion was going on months ago. The fact that some of the external links come from commercial companies do not mean that they are advertisement. he HumanEyes link is at list informatory as the DPL link. I am about to resore it and please leave it. Alternatively, take out the DPL link as well as it is as advertising os the other. In my opinion, these are informative links, they contribute to the content of the article and should stay.

Thanks. —Preceding unsigned comment added by 212.179.74.10 (talk) 12:24, 4 November 2007 (UTC)

I have examined the discussion from your contribs Special:Contributions/212.179.74.10, and it seems that several editors disagreed with you, and this lead to something of a revert war (for example [1]). I agree with these authors in the discussion, and believe that they should be removed. Please can you, as one of the other editors stated, incorporate any useful information into the article. The external links are commercial in nature, all of them (except the lecture notes i put in). I really am sorry, but they do not add to the article and are being used as a promotional vehicle. I think I will need to create a request for comments here to resolve this issue. Kind regards User A1 20:42, 4 November 2007 (UTC)

I totally disagree with you that they "add nothing". But if you are going to blindly ban ANY link to a commercial site, than you need to delete Lenstar as well. They may appear to not be affiliated with a company but who do you think paid for this site? The answer is that one of the major lens manufacturers did and this is a completely commercial site as well. So while I think you are making a real mistake by banning sites solely based on the fact that they are commercial and ignoring whether they have information that is relevant and helpful, if that is your call and you wish to make it, you'll need to ban Lenstar if you wish to be consistent. —Preceding unsigned comment added by 76.81.31.15 (talk) 22:52, 7 November 2007 (UTC)

Sorry, I have messed up the RfC submission and will fix this in about 12hrs. As per the lenstar link, I have removed it a couple of times, if it appears up before this discussion is complete, feel free to move it into the hidden section in the mean time. Thank you for commenting and I will have a chance to more fully address these issues shortly (P.S. don't forget to sign your name with four tilde symbols ~~~~ when you are finished commenting, the editor will substitute the date and time of your comment. Regards User A1 23:14, 7 November 2007 (UTC)

Shorten Manufacturing/expert attention

The section on Manufacturing was merged into the article from Manufacturing technic of a lenticular product following an AfD but although abbreviated from the source is long enough to negatively impact readability of the article. The attention of an expert who can appropriately abbreviate this material would be appreciated. --Moonriddengirl ^(talk) 15:49, 8 December 2007 (UTC)

Water wetting (1° simplification)

by Bernard SOULIER (talk) 15:16, 17 December 2007 (UTC)

UV Ink (2° simplification and internals links)

by Bernard SOULIER (talk) 16:34, 17 December 2007 (UTC)

Water wetting (internals links)

Bernard SOULIER (talk) 17:08, 17 December 2007 (UTC)

Supplement important manufacturing defects of the material lenticular

Bernard SOULIER (talk) 17:26, 17 December 2007 (UTC)

Material removed

I have removed the following uncited claim from the article. If anyone can provide a citation to support it, or better still can put Fraler's work into historical context, please feel free to work it back into the article. What is really needed is an expanded and improved history section.

The term was invented and coined by the physicist Dr. Joseph Robert Fraler from Dallas, TX.

--Srleffler (talk) 20:06, 22 December 2007 (UTC)

SEM image

Hello, With regards to the linked SEM image and its removal - If you take an SEM image, you generally centre the subject. Futhermore you use scalebars that are appropriate to the image, and clearly displayed. The measurements there are very low resolution and frame the information exceptionally poorly. Yes SEM images can be cool, no I don't think these ones are. Also 10kV is a very low accellerating voltage. if those distances as marked are 300um, then this probably would be clearer (and better looking) as an optical image. User A1 (talk) 23:55, 22 December 2007 (UTC)

---

hello, I think the explanation is simple to understand and that the images are also quite clear. 83.201.140.146 (talk) 13:34, 24 December 2007 (UTC)

Besides the comments above, it is not really appropriate to have a whole paragraph in a Wikipedia article that is based on images that are hosted on another site. If you want to have a section discussing manufacturing defects, that's fine, but the images should be released under a suitable license, and displayed inline in the article, not linked to on another site. Note also that conflicts of interest by editors are not acceptable on Wikipedia. Editors are strongly discouraged from linking to their own websites, or their employer's websites. Such links are generally removed very quickly. Persistant linking to a corporate website is likely to result in all links to that site being expunged from Wikipedia.--Srleffler (talk) 02:52, 3 January 2008 (UTC)

Split (and merge)

I think the combination of lenticular corrective lenses and lenticular printing in one article is not helpful. I propose to split this article into two: Lenticular printing, which will contain the bulk of this article's contents, and a second article on lenticular lenses other than those used for lenticular printing (at present the only material we have on that is the section on lenticular ophthalmic lenses). At some point material from Optical lenticular can be merged into the new lenticular printing article, or perhaps it can be kept as a separate article on the physics behind lenticular images. Either way, that article needs a lot of work first.--Srleffler (talk) 20:08, 31 December 2007 (UTC)

Comments?

I think it is a good idea to perform the merge, but some of the printing information can be culled. I am wary of the possibility of copyvio original reserach on the other page, as until now I had never seen that article. As for splitting the printing and physics/optical phenomena, I think that this article should be first merged, then wait a while until the merge is somewhat stable, then re-examine the need to split. User A1 (talk) 05:28, 3 January 2008 (UTC)

I would rather split first, then merge. The need for a separate article on lenticular printing seems clear to me. It's not so clear how or if the material at lenticular optics (formerly Optical lenticular) should be merged in. Besides needing a lot of cleanup work, that article has serious tone and WP:NOT problems. (Wikipedia is not a textbook.)--Srleffler (talk) 18:33, 3 January 2008 (UTC)

Power requirements

Hello,

In the article it states that the UV curing process has an energy density of 200W/cm^2. By my simple calculations this means that for an [ISO_216|A0] page, 1m^2 area, you need (100^2)*200 W of power to cure. This would be 1e4*200W = 2e6W, which is 2MW of power to cure. For a 120V power supply you would need at minimum (ignoring losses) 16.7kA of current (Most houses have 10-20A). If this is coming of a mercury vapour lamp, my understanding is that they take some time to come to steady state, so this would be on for a while.

I realise that without residence time, it may not be valid to make this calculation, as it may be running past a strip light source very quickly and therefore whilst the power density is high, the total power may not be due to the reduced area, but still that's a lot of power density. Is this right?

If I assume that the machine operates via a strip source, of width 1cm, then this reduces the power requirements by a factor of 100, so instead of 16.7kA, we have 167A, which is still a lot of current, although not impossible. Does anyone have a citation for that curing power density? User A1 (talk) 05:58, 3 January 2008 (UTC)

hello, Look at [[2]]90.9.110.105 (talk) 15:11, 3 January 2008 (UTC)

My bad.When cleaning up the section I presumed that the values in W/cm were supposed to be intensities in W/cm². I'm not sure what a W/cm is, but clearly that is the unit that is used.--Srleffler (talk) 18:05, 3 January 2008 (UTC)

As for the reference. I see the numbers but can't understand their context - Unfortunately I don't speak fluent french! User A1 (talk) 23:28, 3 January 2008 (UTC)

I'm not fluent, but I'll take a stab at it:

Ce réflecteur permet, avec une puissance de lampe de seulement 160 W/cm, d'atteindre une vitesse d'impression qui était jusqu'à présent réservée à une puissance de lampe de 200 W/cm. À puissance électrique égale, le rendement de lumière UV peut être augmenté d'environ 20 % sur le substrat par rapport à un ancien modèle.

This reflector permits, with a lamp power of only 160 W/cm, the attainment of a printing speed that was until now reserved to lamp powers of 200 W/cm. Given equal electrical power, the UV light output could be augmented by around 20% at the substrate, compared to an old model.

A little further down, the article discusses another curing system that uses 240 W/cm lamps. The gist of the article seems to be about how performance of curing systems has been improved by ensuring that as much of the lamp's UV output as possible reaches the printing medium, and as little of the infrared, to minimize heating of the medium.--Srleffler (talk) 04:13, 4 January 2008 (UTC)

If it is only quoting the power per unit length of the lamp, I will assume this means it is a strip-based curing technique, whereby relative to the light, the lenticular is moved to perform the curing. If this is the case, we cannot attempt to infer or calculate any power densities in terms of per unit area, as to do this would require knowledge of the lamp geometry and the speed of the lenticular with respect to the lamp. I would suggest this claim requires alternate data. User A1 (talk) 10:48, 4 January 2008 (UTC)

Nomenclature

Prior to linking to the "Autostereoscopy" article from the article about Frederic E. Ives (the inventor, or at least one of the inventors, of the parallax barrier method) I am inclined to replace occurrences of "lenticular lens" in the former with alternatives and state the following in the edit description:

"Lenticular lens" is a bizarrely redundant (see the Merriam-Webster definition of "lenticular") and non-descriptive coinage of relatively recent origin which ought to be avoided.

To spare anyone a run to the dictionary: "lenticular" means (1) shaped like a double-convex lens (from the Latin "lenticularis" meaning "lentil-shaped" and from the root of which the word "lens" derives); (2) of or relating to a lens; (3) having lenticules, e.g., a lenticular screen. So in the first two senses a "lenticular lens" is a lens-shaped lens or a lens-like lens or a lens-related lens.

The only optical component which can reasonably be described as a "lenticular lens" is a comparatively large lens with one or more smaller lenticulations on at least one of its surfaces, so it may indeed be a proper description of the corrective lenses mentioned, even if the supporting "lens" is zero-diopter. However, unless used very close to the eye, a flat piece of plastic does not qualify as a "lens" and to describe the lenticular sheets/arrays/screens/matrices/panels/coatings/overlays used for displaying 3-D and/or motion as "lenticular lenses" is a linguistic abomination.

As a dinosaur who was researching and tinkering with lenticular processes in the 1970s, I can testify that the term was not apparent back in that era, which was rife with lenticular novelties. I suspect it would be difficult to find it used in this sense in any present-day technical journal. It has the air of having been carelessly used to describe lenticular sheeting in some popular and authoritative-seeming publication or website, leading novices to believe it was standard terminology and causing it to go viral.

I will hardly be surprised if any such edits to the "Autostereoscopy" article are quickly reverted and I have no intention of waging any wars over this. The subject of 3-D is not the Wikipedia topic which I am tackling. However, I would respectfully suggest that Wikipedians working on this topic should consider whether helping to confine the use of "lenticular lens" to the optician's office might be rendering a service to mankind, or at least to 3-D enthusiasts.

AVarchaeologist (talk) 06:08, 21 September 2010 (UTC)

We don't prescribe usage here; by policy Wikipedia follows and documents common usage. It doesn't matter if a term is a linguistic abomination; if it is the term that is in common use, it is the term we will (and must) use. If there are alternate terms that are used in reliable sources, feel free to introduce them as well.

I did add a request for a citation supporting the use of the term. There aren't currently any reliable sources cited that use "lenticular lens" for a non-ophthalmic device.--Srleffler (talk) 03:56, 22 September 2010 (UTC)

Incorrect figure

New version

I think the second figure has a few issues. http://en.wikipedia.org/wiki/File:Parallax_barrier_vs_lenticular_screen.svg

While it is an attractive graphic, I think these should be changed:

1. Use 3 lenses instead of 4.
2. The L/R images need to be flipped.
3. The refraction cones need to be swapped.

Compare to this to see the differences: http://www.3d-forums.com/attachments/lenticular-gif.8/ My understanding is that the 3d-forums image is correct.

I've had a stab at changing it myself, but my Inkscape isn't very good: https://dl.dropboxusercontent.com/u/46629779/Parallax_barrier_vs_lenticular_screen_correct.svg

All three of these images are horribly flawed. I agree with you that it is an error that the one in the article has four lenses but only three left-right image segment pairs. Each lens should have one pair of left and right image slices, as in your version.

I don't understand your second and third objections. There are problems with the light cones in the image, but yours are not better. In particular, the light from each image slice goes through the whole lens, not just the half of the lens above it, as in your image. The image in the article is correct in having fans of light from each image slice that fill the whole lens and arrive at the appropriate eye. The 3D forums image is terrible in that it doesn't show any refraction by the lenses. This is important, because it is the refraction at the lens surfaces that makes the lenticular array work. The image looks meaningful, but isn't.--Srleffler (talk) 01:34, 18 July 2013 (UTC)

Hi, thanks for the reply Srleffler. You're right that my image and the 3d-forums image aren't great, either! Sorry about that. My second objection was that I thought the multiplexed image on the back plane should be flipped to achieve the right effect (from left-to-right, the pixels should be interleaved right-eye-image then left-eye-image). My third objection was just a consequence of the second.

There's a need to be 'simple', but how about instead something that showed zones of intersection where binocular stereo is visible, and the eyes floating within these zones rather than rays going to the eyes? ----Jamestompkin (talk) 04:46, 24 July 2013 (UTC)

I see. For each lenslet, the "left" image should be on the right, and vice-versa. In the picture, the ray fans through the middle two lenses are correct and the image slices are correctly placed. The picture only shows one image slice for each of the outer two lenses, however, and they don't look like they are correctly aligned. It is possible that they are actually correct, but that the alignment looks wrong because of the angle of view and the odd 3D perspective.--Srleffler (talk) 01:20, 25 July 2013 (UTC)

Thanks for the feedback, Srleffler and Jamestompkin. I hope I've addressed my mistakes as on the right. Do you have any other objections? If not, I'll put it back in the article in the next few days. By the way, https://dl.dropboxusercontent.com/u/46629779/Parallax_barrier_vs_lenticular_screen_correct.svg gave me an Error (404). cmɢʟee୯ ͡° ̮د ͡° ੭ 18:46, 21 August 2013 (UTC)

It is better. The alignment between the image segments and the lenses still doesn't look quite right. Each lens should have an "L" and an "R" image segment behind it, and the image segments shouldn't stick out at the ends of the lens array. --Srleffler (talk) 06:45, 25 August 2013 (UTC)

Hi Srleffler, can you please give a reputable source for "Each lens should have an "L" and an "R" image segment behind it, and the image segments shouldn't stick out at the ends of the lens array"? I think geometric optics dictates that the image segment has a slightly lower frequency than the lens array (probably negligible compared to the distance from the eye to the lens, but not at the scale of my drawing). http://www.3d-forums.com/attachments/lenticular-gif.8/ does not fully address this as it has just straight lines connecting the segments to the eyes regardless of the lens. cmɢʟee୯ ͡° ̮د ͡° ੭ 12:59, 6 September 2013 (UTC)

I don't have a source for my comment, but I don't need one since this is a talk page. It seems fairly obvious to me that the image segments need to have the same frequency as the lenses, otherwise they would get out of synch across the array. The problem is evident even on the small image section you show: the "L" image slice that sticks out at the right end of the diagram is way too far to the right. Almost none of that slice is behind the rightmost lens shown. The majority of the slice is behind the next lens to the right, which is not shown. Light from that image slice passing through that lens would be directed toward the viewer's right eye. --Srleffler (talk) 05:25, 7 September 2013 (UTC)

Geometry of insect eye

What about to compare with the geometries found in the eyes of insect eyes, developed by nature? --Helium4 (talk) 09:16, 21 October 2015 (UTC)

Strong definition needed for "Lenticular lens"

Current source is [3]. There is no "Lenticular lens" as separate term. Halfcookie (talk) 20:48, 20 May 2017 (UTC)

You've raised a good point. Maybe we just need to find a better title for this article, or maybe we need to do something more drastic. There is a lot of topical overlap between this article and lenticular printing. Much of the content here could be merged into that article. I'm not what to do then with the material on lenticular screens, and on corrective lenses.--Srleffler (talk) 21:33, 20 May 2017 (UTC)