Good point, and I agree heartily. However, I'm not suggesting you use a single LED to illuminate an entire image -- you SCAN the image, and rely on human image retention in the eyeball to make it look like a solid image. That'd be one key question -- whether you can scan fast enough to do this. You might even need to double-scan images (twice per visual field) or somesuch.
So you are going to use the LED to illuminate one pixel at a time. For a 640x480 screen there are more than 300,000 pixels. At 30 frames/sec, each pixel is going to be illuminated for around 0.11 microseconds.
The problem is the eye has an integration time of about 1/30th of a second, but the pixel is only illuminated for 0.11 microseconds. This is equivalent to integrating the same illumination level for the 0.11 micro second time. But when you are just shining the LED on the wall you are integrating to the full 1/30th of a second. The let's assume the illumination level is 1. So the integral for the Photon on the wall is 1 integrated for 1/30 of a sec or.033. For your scanning LED the integral is 1 integrated for 0.11 microsencond or.00000011.
For a given pixel size, this means you need to make the light 300,000 brighter if you scan it than if you don't if the eye is going to see the same amount of light.
Your TV solves this problem by having a phosphorous surface on the back of the screen. A powerful electron beam excites the phosphorous and then moves on. The phosphorous holds the image while the electron beam is elsewhere.
The Eye View system is an early version of a system designed to create full 3-D models of live action. The idea is if you film a scene from enough different angles you can create a 3-D model and play it back from any virtual camera position you want.
I thought Eye View was pretty neat. Yes the it was jumpy, yes it was grainy but it did do a good job of showing what was going on about half the time they used it. The article I read about said that if they only used it 3 times they would be happy, well they used it a lot more than 3 times.
I have an additional piece of information.
I work for a large educational institution. For small purchases (less that $1000) we have purchasing credit cards. About half the employees in my department have their own cards. Many of them have been used at egghead. About half of those cards had unauthorized transaction from the same company in Russia. Of the card that had not been used at egghead, none had similar transactions. This seems like more than a typical set of unauthorized transactions. Personal cards in the office had the same trend.
Now given the amount of online ordering that we do, some other database could have been hacked. But it all seems a bit fishy to me. BTW the bank automatically canceled all cards that had been used at Egghead. It would be interesting to see how many transaction were tried after the cards were canceled.
Having been a mentor for First and judging for First Lego League, I just couldn't let this comment stand.
There are 2 different competitions. The High School League and the First Lego League.
The High School league involves making a robot, that is about 3ft x 3ft x 3ft, from stock materials (basically anything you can get at a hardware store.) Everything a team uses on a robot has to be documented and on an approved list of materials. These lists are used to keep the teams on an equal footing. The list for electronics is very small. But there is some real work to get all the electronics you want, with what you are allowed.
You do need to program you robot. Robots are tele-operated and run from 2 joysticks and several discrete switches and buttons. The processing is done by a basic stamp but First provides a control module that gives you DACs, and PWMs out of the Stamp. First gives you a basic program that will run everything but not very well. A good CS person can do a lot to make the robot run better based on changes to the code. Most of the work would be in low level control code not in high level AI type stuff.
The competition that really impressed me was the First Lego League. The competition is for middle school age kids. The teams make robots out of Legos using the Mindstorms RCX box as a controller. These robots are autonomous. The kids program the robots to do different tasks. Once the robot returns to a certain section of the playing field the kids can change the program and reconfigure the robot. This competition really requires some CS skill. Here the teams are limited to the parts that come with the Lego Robotics Inventor Kit. Judging this competition convinced me to go out and buy Mindstorms for myself.
With both competitions the real key is have a coach (and/or mentor) that really leads the team. When I judged the PA state finals you could tell the difference between a team that had a coach that did nothing, a coach that did everything, and coach that guided the kids but left that actual design and choices to the kids. The kids with a coach in the last category, were having the most fun and learning the most.
Beyond coaching, the kids get out what they put in. If a kid decides he wants to program, reads up on what he can do, how he can do it, and then does it, he can fill the whole time doing CS type stuff.
If you are interested in using robotics for education or are in middle or high school and are interested in robotics take a look at http://www.rec.ri.cmu.edu/education/
While I agree that an email to a congress person is not as effective as a snail mail, an email on this issue says something that a snail mail can not. The law being considered came about because the internet has gone main stream. Enough people use the internet that issues regarding internet, and its use are effecting politics. Its time to tell the congress people that the time is coming (if not already here) when the internet has a direct effect on politics. An email says 'this is an issue about the internet, so I am going to use the internet to express my feelings about it.'
My suggestion is to join the 'Million E-mail March.' Send the email, but don't send a form E-mail. Remember, they hate form letters just as much as we do. Send them a well thought out email, in your own words. Be polite, clearly state your feelings about the subject, and make it clear how you feel they should vote. Then Send them a snail mail that talks about how you feel email is not as influential as it should be. Say something to the effect of:
I recently sent you an email about < insert your issue here >. I feel so strongly about this issue that I am following it up in snail mail because I am concerned that your office does not take email seriously enough. I feel email and the internet are the best way to reach and communicate with you constituents. By using the net you can listen to how your constituents feel about particular issue that are going on today. By using this valuable resource you will be able to better represent your congressional district.
I have enclosed a hard copy of my previous email regarding < insert your issue here >.
If enough people send a letter like that we might actually bring government into the internet age.
And on this issue make sure you state that you feel the same way about books, movies, and other audio formats. It would be a shame to be allowed to make MP3 copies but not wave files.
I remember having the college/work conversation (argument) with my parents my senior year of high school. I was sure that I wanted to be a theater techie. I was even building a fairly good name for myself doing it. (I was starting to get union overhire calls.)
I ended up going to college. I was majoring in Drama Production and I hated it. I almost dropped out. But I convinced my advisor to let me take some courses outside the drama department. (CMU's drama department does not give you much flexibility or recognize outside interests) Anyways I started taking ECE and CS classes. After a bit I changed majors to ECE and started working in robotics. I even did something that I thought I would never do, I got my Master Degree.
If I had not gone to college I would be hating life in a dark theater making peanuts. Now I have met some of the most brilant people I have ever known and I can have great conversation with them. I look at the world in a whole different way. Furthermore I have in depth conversations with people who have been in the computer field longer than I have been alive because I know the theory and the ways of thinking behind what they do. If you are working on the cutting edge you are going to have to be learning new technology. With a college degree you can understand it without a '{string} for Dummies' book. Finally the is just as much smoke and mirrors in research robotics and in the theater, the technology is just much much cooler.
BTW My dad dropped out of college after a year and makes a killing in the computer industry. Just show there is never a correct answer to a question like this.
Katz gets it totally right and totally wrong with this point
... they want information of particular interest to them, at the times they choose to receive it. They demand the right to alter the media they receive. Older Americans raised on passive, pre-interactive media -- papers, newsmagazines, TV news that offer few choices and little control -- are much more likely to stick with traditional news.
The problem with TV news is that someone else chooses what I get to see and when I get to see it. Papers and magazines let me choose what I want as long as it is at least x amount of time after the event (6 hours for papers, 36 for magazines.) But the internet lets me choose what I want, when I want it and is current, frequently more current than anything else. The TV news frequently doesn't have anything from the last 2 hours in it. The breaking news on the 11 o'clock news happened around 8 o;clock.
I do not consider papers and magazines "pre-interactive." While you cann't alter them, they are very interactive. You can choose what stories to read and how much of them you want to read. They just have a time delay.
I read the paper for news, magazines for analysis, and use the internet for breaking news. Of course I use/. for thing that would never make it into the other three.
Slashdot Mirror
The problem is the eye has an integration time of about 1/30th of a second, but the pixel is only illuminated for 0.11 microseconds. This is equivalent to integrating the same illumination level for the 0.11 micro second time. But when you are just shining the LED on the wall you are integrating to the full 1/30th of a second. The let's assume the illumination level is 1. So the integral for the Photon on the wall is 1 integrated for 1/30 of a sec or
Your TV solves this problem by having a phosphorous surface on the back of the screen. A powerful electron beam excites the phosphorous and then moves on. The phosphorous holds the image while the electron beam is elsewhere.
The Eye View system is an early version of a system designed to create full 3-D models of live action. The idea is if you film a scene from enough different angles you can create a 3-D model and play it back from any virtual camera position you want.
I thought Eye View was pretty neat. Yes the it was jumpy, yes it was grainy but it did do a good job of showing what was going on about half the time they used it. The article I read about said that if they only used it 3 times they would be happy, well they used it a lot more than 3 times.
The full 3-D system is being developed at Carnegie Mellon University and Zaxel Systems
Now the half time show sucked rocks. It was a 10 minute concert not a half time show. Maybe DCI should do a half time.
I have an additional piece of information. I work for a large educational institution. For small purchases (less that $1000) we have purchasing credit cards. About half the employees in my department have their own cards. Many of them have been used at egghead. About half of those cards had unauthorized transaction from the same company in Russia. Of the card that had not been used at egghead, none had similar transactions. This seems like more than a typical set of unauthorized transactions. Personal cards in the office had the same trend.
Now given the amount of online ordering that we do, some other database could have been hacked. But it all seems a bit fishy to me. BTW the bank automatically canceled all cards that had been used at Egghead. It would be interesting to see how many transaction were tried after the cards were canceled.
Having been a mentor for First and judging for First Lego League, I just couldn't let this comment stand.
There are 2 different competitions. The High School League and the First Lego League.
The High School league involves making a robot, that is about 3ft x 3ft x 3ft, from stock materials (basically anything you can get at a hardware store.) Everything a team uses on a robot has to be documented and on an approved list of materials. These lists are used to keep the teams on an equal footing. The list for electronics is very small. But there is some real work to get all the electronics you want, with what you are allowed.
You do need to program you robot. Robots are tele-operated and run from 2 joysticks and several discrete switches and buttons. The processing is done by a basic stamp but First provides a control module that gives you DACs, and PWMs out of the Stamp. First gives you a basic program that will run everything but not very well. A good CS person can do a lot to make the robot run better based on changes to the code. Most of the work would be in low level control code not in high level AI type stuff.
The competition that really impressed me was the First Lego League. The competition is for middle school age kids. The teams make robots out of Legos using the Mindstorms RCX box as a controller. These robots are autonomous. The kids program the robots to do different tasks. Once the robot returns to a certain section of the playing field the kids can change the program and reconfigure the robot. This competition really requires some CS skill. Here the teams are limited to the parts that come with the Lego Robotics Inventor Kit. Judging this competition convinced me to go out and buy Mindstorms for myself.
With both competitions the real key is have a coach (and/or mentor) that really leads the team. When I judged the PA state finals you could tell the difference between a team that had a coach that did nothing, a coach that did everything, and coach that guided the kids but left that actual design and choices to the kids. The kids with a coach in the last category, were having the most fun and learning the most.
Beyond coaching, the kids get out what they put in. If a kid decides he wants to program, reads up on what he can do, how he can do it, and then does it, he can fill the whole time doing CS type stuff.
If you are interested in using robotics for education or are in middle or high school and are interested in robotics take a look at http://www.rec.ri.cmu.edu/education/
My suggestion is to join the 'Million E-mail March.' Send the email, but don't send a form E-mail. Remember, they hate form letters just as much as we do. Send them a well thought out email, in your own words. Be polite, clearly state your feelings about the subject, and make it clear how you feel they should vote. Then Send them a snail mail that talks about how you feel email is not as influential as it should be. Say something to the effect of: If enough people send a letter like that we might actually bring government into the internet age.
And on this issue make sure you state that you feel the same way about books, movies, and other audio formats. It would be a shame to be allowed to make MP3 copies but not wave files.
I remember having the college/work conversation (argument) with my parents my senior year of high school. I was sure that I wanted to be a theater techie. I was even building a fairly good name for myself doing it. (I was starting to get union overhire calls.)
I ended up going to college. I was majoring in Drama Production and I hated it. I almost dropped out. But I convinced my advisor to let me take some courses outside the drama department. (CMU's drama department does not give you much flexibility or recognize outside interests) Anyways I started taking ECE and CS classes. After a bit I changed majors to ECE and started working in robotics. I even did something that I thought I would never do, I got my Master Degree.
If I had not gone to college I would be hating life in a dark theater making peanuts. Now I have met some of the most brilant people I have ever known and I can have great conversation with them. I look at the world in a whole different way. Furthermore I have in depth conversations with people who have been in the computer field longer than I have been alive because I know the theory and the ways of thinking behind what they do. If you are working on the cutting edge you are going to have to be learning new technology. With a college degree you can understand it without a '{string} for Dummies' book. Finally the is just as much smoke and mirrors in research robotics and in the theater, the technology is just much much cooler.
BTW My dad dropped out of college after a year and makes a killing in the computer industry. Just show there is never a correct answer to a question like this.
Katz gets it totally right and totally wrong with this point
... they want information of particular interest to them, at the times they choose to receive it. They demand the right to alter the media they receive. Older Americans raised on passive, pre-interactive media -- papers, newsmagazines, TV news that offer few choices and little control -- are much more likely to stick with traditional news.
/. for thing that would never make it into the other three.
The problem with TV news is that someone else chooses what I get to see and when I get to see it. Papers and magazines let me choose what I want as long as it is at least x amount of time after the event (6 hours for papers, 36 for magazines.) But the internet lets me choose what I want, when I want it and is current, frequently more current than anything else. The TV news frequently doesn't have anything from the last 2 hours in it. The breaking news on the 11 o'clock news happened around 8 o;clock.
I do not consider papers and magazines "pre-interactive." While you cann't alter them, they are very interactive. You can choose what stories to read and how much of them you want to read. They just have a time delay.
I read the paper for news, magazines for analysis, and use the internet for breaking news. Of course I use