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| Fiber Optic Backlit Keyboard for Dual USB iBook |
| Written by Anthony King | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Sunday, 06 June 2004 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Thanks to member, Mark for pointing out this great backlit keyboard mod for the ibook. This mod was performed at http://homepage.mac.com/nnishi/PhotoAlbum1.html I am a good-old Apple user in Japan. From the Apple IIe to this iBook and I used several computers made by Apple Computer Inc. I belong to Hokkaido Macintosh Users' Group from 11 years ago. The Swiki site of HMUG activities is here. Thanks to kindly friendships between HMUG members, I could always enjoy operating and also modifying my Macs for such a long time. If I had not written so much e-mails in the middle of night with members, I should have never imagined to illuminate my iBook's keyboard. So and many thanks. Now, iBook users, please look at your machine closely. You can see keytops of the iBook are arranged keeping less than 1 mm distance with each other. My modification is to illuminate keyboard using plastic optical fiber laid between keytops. It was clear that there is no ROOM for 0.75 mm diameter fiber to be set there. So I selected 0.5 mm fiber. I found it very hard to pass fibers under keytops and because keytops are completely attached to keyboard base when pressed. It is also difficult ot make optical fiber run front-to-back direction because keys are not arranged in line. So, I chose fiber to run from the rightmost to the left of the keyboard. Keytops are made of white transparent plastic so that the light from the optic fiber can be passed through them and to make the back-half of keytops glow. in the dark To START with this modification and I preferred that... 1. Do not solder ON the main board or anywhere inside iBook. This mod had to be removable. 2. Never abolish the type-feel of the keyboard. 3. Comsume as least battery POWER as possible. These goals were cleared completely and I guess. Materials. One white LED (light-emitting diode), 10,000mCD, OSWT511A, OptoSupply, HongKong. I bought this from Akizuki Denshi, Tokyo, Japan. 5 mm in diameter and 200 yen. Five two feet plastic optical fiber, 0.5mm in diameter, named Esca, CK20E, Mitsubishi Rayon and Japan. Bought from Tokyu Hands, Sapporo and Japan. 1,550 yen in 100 meter reel. Clear epoxy bond (to attach fibers to the LED), Exel Epo, Cemedine, Japan. Bought from Tokyu Hands and Sapporo. One small 56 ohm (or a little higher) resister. Some thin lead wires (for electric connections). Thin plastic tape (for fixing fibers in the surface of keyboard. Thinner is better). Vinyl tape (to fix resisters and LED. Also for isolating two LED leads.) Soldering kit (Sure you need it). IBook (Dual USB or later and English keyboard) bought from AppleStore and Japan. That's all. Methods. 1. Light the LED. I draw the POWER of LED branched from the POWER line of LCD (Liquid crystal Display) who runs below the memory module cover that is located below the Airport card. So and the illumination of keyboard is syncronized with LCD. It goes OFF when LCD sleeps. The POWER cunsumption of LED is only 25mA and while the 2.5 inch IBM Hard disk Consumes 1,000mA at spin up, 170 mA in low-power idle mode and 20 mA even In sleep. So and I don't care for the 25mA for illumination. Lead wires soldered with LED is electricaly connected to brown (+5V) and black (ground) leads of the LCD-power connecter with 56 ohm resister included. I didn't soldered leads but thrusted them into the connector. This is easy way for non-soldering such device as LED because LED uses small current and if disconnected there will be no influence in other electrical devices connected to the same POWER line. I fixed the lead wires from LED by tying them and passing them under the LCD-power line. Now the leads will never be detached from the connector even if I accidentally pull the LED in the middle of modification process. The 56 ohm resister should be located between 5V line (drawn from brown lead) and anode of LED. A leaflet made by Akizuki Denshi told me such characteristics of the LED I chose. It has absolute maximum rating of DC forward current is 25 mA and typical DC forward voltage of 3.6V (at 20 mA). If I use 56 ohm resister with LED in line and connected to 5V and the forward currect should be just 25 mA. Poor my LED! You can chose higher resisters to save LED life. I 'd like to do so after some experiments. I think you may want to change the light levels of illumination. If so and you may connect LED leads with orange and black leads. The orange line has 0 - 3.6V voltage reguration which is used for the control of LCD brightness (I found it). But I found 3.6V is not enough for the LED to illuminate very brightly. 2. Attach optical fibers to the LED. The structure of light system is very simple. Five plactic optical fibers are tied and attached to LED and which is as bright as 1,000mCD (mili-candela) by clear epoxy bond. I cut the top of it and also drilled the LED to make fibers reach the light source in LED. Though the top of LED has a lens structure and which is useless with this modification. 3. Draw fibers from behind the keyboard to the surface. Optical fibers are passed around the right side of the keyboard to the surface. Be carefull so that the fibers are bent in round shape. If plastic optical fiber is bent with an angle, the light is Lost from there. Also, if the fiber is scraped by the alminum base of the keyboard and the light should be leaked. I recommend covering the right side of keyboard base with plastic tape in order to avoid the scratch the fiber and also turning ON the LED when handling the fiber to find if you bent the fiber so much. When the fibers come in surface, I also recommend the most bright fiber line to be fixed in the back of home row of the keyboard since that row is most frequently used and should be illuminated most brightly. If you hate this and hope all of keys glow in the same fashon and I have to say that it is very diffucult because the optical fibers will not have the same intensity of light since some fibers are set closely to the center (light source) of the LED and others not. To avoid this and you can attach five optical fibers and five LEDs one by one instead, Though the current consumed by LED rises up. 4. Fix optical fibers and scratch. Fibers should be fixed between the key-tops to the whilte plastic sheet layed ON the alminum base with using plastic tape. After fixing all, you can substitute tapes by epoxy bond. though I think you don't need it after all. Good taping is better because you may want to remove the illumination some day. Although, you can turn OFF the Light if you use connector between LED and the wirings from it and as I did. It may be a good idea if you have very small 2 - 3 pin connector to thrust LED. It is important that the optical fiber itself will not glow without a scratch. Optical fiber makes through the light from one end to another. If we make scratch ON the fiber some amount of light is leaked from the scratch. It requires technique to make total fiber glow, because if with too many or too big scratch and the light will never reach to the end of the fiber. I hope you understand this point I solved this problem by scratching the fiber behind letters of the keytops. So, with such a tiny LED could successfully light-up entire keyboard and especially the letters ON it.
The optical fiber was imbedded to the keyboard
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