Archive for September, 2011

Care about your offer letter

解密Offer Letter:每一项和每个数字都意义重大

Offer Letter should conclude the following key parts:

  1. Base Salary: 这与你的学历、经历以及能力等综合因素息息相关
  2. Bonus: Offer Letter上面会列出基本的比例系数,比如10%,也就是说奖金的基本值就是你底薪的10%,然后根据公司和个人每年Performance的状况,由 公司来决定每年(或半年)度的奖金系数。公式是: 个人年度奖金 = 个人底薪x基本奖金系数x Performance系数。年景有好坏之分,但公司通常的奖金系数范围还是比较固定的,特别是对于有些底薪不高的公司,往往以高于同侪的奖金来吸引人 才。作为参考,奖金高的能达到年薪的45%以上,低的甚至没有
  3. Sign-on Bonus: 通常在签约后一个月左右发放,数量从几千到数万美元不等。需要说明的是,这种签约奖金一般都是有年限规定的,也就是签约者必须在该公司工作满一定的时间, 比如一年或两年。 如果不到期满就另择他就的话,则需要根据剩下时间段所占的比例来退还给公司
  4. Stock:
  • RSU(Restricted Stock Unit): 这也就是国内常说的“干股”。即公司将股票作为礼物赠送给你,个人不需要任何资金的投入,而最后的收益是所有这些股票的市场价值,公式是: RSU收益 = RSU配股数x股票卖出时市场价。要注意的是,RSU通常是逐年发放的, 比如一共是一千股的RSU,可能会以每年250股的配额,分四年时间来发到你的个人帐户, 如果提前跳槽,剩下的RSU就拿不到了。此外,股价有涨有跌,什么时候卖出股票就需要自己take care了,这也影响了最终的RSU收益
  • Option: 也就是常说的股票期权。和RSU不同的是,依据公司配给Option时的市场价,最后的收益为这些股票卖出时市场价和配股时市场价的差,公式 为:Option收益 = Option配股数x (股票卖出时市场价-股票配给时市场价)。和RSU一样,Option也是逐年配给的,也不需要任何个人资金的投入。唯一的区别是,收益是前后两次的股票 价格差,当股票市场价格低于配入时价格时,收益为零
  • ESPP(Employee Stock Purchase Plan): 员工股票购买计划。即在美国的公司员工,可以以低于市场价的价格购买本公司股票,通常是以一季度为期,取三个月的首日以及最后一天的股价,两者间取较低值为基准,再加上15%的折扣,作为配给员工的ESPP股价,而配给的股数上限一般是员工季度工资的10%。与RSU以及Option相同的是,ESPP也需要个人及时关注并卖出;不同的是,ESPP需要个人资金的投入,自负盈亏的色彩更明显

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3D technology……

3D technology basis

There are lots of ways to achieve a 3D display. Most of them are based on simple principal – display a different image to each eye, and so create the illusion of a 3D image.

Generally, there are following 3D implementation:

  1. In the old days(Anaglyph 3D)

Probably the easiest way to make 3D images is to separate the right and left image using colors. The image has two color “layers”, and you separate the layers using glasses that has blue/red lenses (or cellophane paper, in the cheapest glasses). This is called Anaglyph 3D, it’s cheap and easy to do as you don’t need a new TV and the glasses are very cheap. The problem is that you lose colors in the image. It simply looks bad.








  1. Polarized(Passive 3D)

A Polarized 3D uses a polarizing filter on the image so the left and right images each has a different polarization. You use passive glasses that filter the right image for each eye. This technique is popular in the cinemas using two synchronized projectors. Making a polarized 3D LCD panel is not easy as the LCD already has a polarizing filter, and you lose half the resolution, but it is possible. LG for example seems to be better on polarized LCDs as their leading 3D technology. One of the advantages of passive glasses is that they are very cheap.










  1. Shutter 3D(active)

The new breed of 3D TVs and projectors make use of a simple idea – you display images for the left and right eye alternatively – once the image for the left eye, and once for the right. Now all you have to do is wear glasses that block each eye in sync with the display, and you get 3D. Active Shutter 3D glasses main advantage is that the image looks great – just as they look in 2D on the same display.

Active-3D is costly, though. The display must refresh the screen fast enough – at least 60Hz for each eye, which means 120Hz for the display itself. The glasses are also expensive (over $100 usually) – they have to include 2 LCDs, and batteries. And you also has to synchronize the display to the glasses (usually using Infra-red).

In short – you must get a new TV (or projector) that supports active-shutter glasses. It is projected that within a few years, most TVs on the market will support this new 3D technology, and most TV makers (including Sony, Samsung, LG, Toshiba, JVC and Panasonic) have already selling high-end models that are 3D-enabled.








  1. No-glass 3D(Auto-Stereoscopic)

Auto-Stereoscopic displays display different pixels to each eye, using optics (lenses or barriers) to direct the correct pixels to each eye. The nice part is that you don’t need to wear any glasses to experience the 3D image! But there are many problems with these new kinds of technologies. Basically there is just one location you can be in order to view the 3D correctly (just one viewpoint). You can add more viewpoints, but each viewpoint actually requires two ‘dedicated display’. This means that if you want 10 places from which you can view the 3D, you need to be able to produce 20 sets of displays – that’s a lot of pixels. Another issue is that the display is always in 3D. You can’t view a 2D image. There are some solutions to that, too (for example Sharp is using 2 sets of LCD layers – one for 3D and one for 2D, and you can turn off the one you do not want to use).

These technologies are starting to appear now commercially, but don’t hold your breath for a 3D TV for home use that will not require glasses – it will probably take a few years as the technology is very costly currently, is usually limited in the number of ‘viewpoints’ it provides and the quality isn’t as good as polarized or active-shutter 3D…

To be continued……

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