On the Photocomparator (ASIA KRC) and the Stereo 
Pricking Device (ASIA KRP) 
By 
Tamanosuke Kuramochi* 
Introduction 
Since an electronic computer had come to the fore, it has found wide uses in 
every branch of industry into which modern management is intended to be intro 
duced. In 1958, Asia Air Survey (Co., Ltd.) has taken the initiatives in introduc 
ing it in to themselves and started to bring about a tendency of making use of 
it actively. 
About six years ago I have got an idea for the design of photocomparator 
(ASIA KRC) and stereo pricking device (ASIA KRP), the report of which will be 
presented hereunder. 
In order to get the coordinates of points by analytical arerial triangulation 
and to obtain the elements of orientation, it is a necessary matter that machines 
may be brought into being which meets these new requirements. First of all, we 
intended to measure precisely the photo coordinates of the points fixed as tiny 
holes on diapositives which were pricked by means of needles of proper size pre 
viously. It is evident that the clear traces of points on diapositive will help 
extremely the orientation work of plotting machine which shall be carried out 
necessarily on the occassion of map plotting. Effort had to be directed to the 
simplification, specialization, standardization and the reduction of the costin order 
to satisfy the above intention. 
In the case of photocomparator, therefore, movements were only confined to 
the 2 orthogonal direction X, Y and the revolving mechanism was saved and com- 
mited to the coordinate transformation by electronic computer. Instead of using 
streocomparator, stereoscopical observations are done by pricking device and this 
separation of operation in 2 stages led to the reduction of motions for comparator 
from 6 (X u Y u X 2 , Y 2 , Ku K 2 ) to 2 (X, Y). Since in such a way, streoscopical 
observation is conducted when pricking is carried out which is the process to be 
performed prior to the coordinate measurement and a pair of cooresponding points 
shall be pricked on each of the adjacent photograps, it was concluded that there 
was no need of conducting streoscopical observation on the photocomparator itself 
and it was decided to simplify so as to be provided only with the mechanism 
necessary for the measurement of single photograph (single diapositive). It is 
needless to say that an electronic coordinate recorder as well as a perforating de 
vice have been attached thereto. This enables also, on the other hand, to simplify 
and to make precise the pricking device without calling for the provision of meas 
uring mechanism. In consequence, I was confident of the facts that it would be 
* Chief Researcher; Asia Air Survey Co., Ltd. Tokyo, Japan.